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                                                                    Exhibit 4.23

                                                                            FORM

                                   ONEOK, INC.

                                     Issuer

                                       and

                                  SUNTRUST BANK

                                     Trustee

                          JUNIOR SUBORDINATED INDENTURE

                            Dated as of [__________]

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                                   ONEOK, INC.

     Reconciliation and tie between the Trust Indenture Act of 1939, as amended
(the "Trust Indenture Act") (including cross-references to provisions of
Sections 310 to and including 317 which, pursuant to Section 318(c) of the Trust
Indenture Act are a part of and govern the Junior Subordinated Indenture dated
as of [__________] (the "Junior Subordinated Indenture") whether or not
physically contained therein), and the Junior Subordinated Indenture.

                                 Trust Indenture
                                  Act Section                 Indenture Section

     (S) 310(a)(1), (2) and (5)                               6.9
     (a) (3). ...........................................     Not Applicable
     (a)(4). ............................................     Not Applicable
     (b). ...............................................     6.8
                                                              6.10
     (S) 311(a) .........................................     6.13
     (b) ................................................     6.13
     (b) (2) ............................................     7.3(a)
     (c) ................................................     Not Applicable

     (S) 312(a) .........................................     7.1
                                                              7.2(a)
     (b) ................................................     7.2(b)
     (c) ................................................     7.2(c)
     (S) 313(a) .........................................     7.3(a)
     (b) ................................................     7.3(a), (b)
     (c) ................................................     7.3(a), 7.3(b)
     (d) ................................................     7.3(c)
     (S) 314(a)(1), (2) and (3) .........................     7.4
     (a)(4) .............................................     10.5
     (b) ................................................     Not Applicable
     (c)(1) .............................................     1.2
     (c)(2) .............................................     1.2
     (c)(3) .............................................     Not Applicable
     (d) ................................................     Not Applicable
     (e) ................................................     1.2
     (f) ................................................     Not Applicable
     (S) 315(a) .........................................     6.1(a)
     (b) ................................................     6.2
                                                              7.3(a), (b)
     (c) ................................................     6.1(b)
     (d) ................................................     6.1(c)
     (d)(1) .............................................     6.1(a)(1)
     (d)(2) .............................................     6.1(c)(2)
     (d)(3) .............................................     6.1(c)(3)
     (e) ................................................     5.14

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                                Trust Indenture
                                  Act Section                 Indenture Section

     (S) 316(a) ........................................      1.1
     (a)(1)(A) .........................................      5.12
     (a)(1)(B) .........................................      5.13
     (a)(2) ............................................      Not Applicable
     (b) ...............................................      5.8
     (c) ...............................................      1.4(f)
     (S) 317(a)(1) .....................................      5.3
     (a)(2) ............................................      5.4
     (b) ...............................................      10.3
     (S) 318(a) ........................................      1.7

          [Note:  This reconciliation and tie is not and shall not, for any
          purpose, be deemed to be a part of the Junior Subordinated
          Indenture.]

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                                TABLE OF CONTENTS

<TABLE>
<S>                                                                                               <C>
ARTICLE I DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION ..........................       1
  Section 1.1 Definitions ..................................................................       1
  Section 1.2 Compliance Certificate and Opinions ..........................................      10
  Section 1.3 Forms of Documents Delivered to Trustee ......................................      11
  Section 1.4 Acts of Holders ..............................................................      11
  Section 1.5 Notices, Etc. to the Trustee and the Company .................................      13
  Section 1.6 Notice to Holders; Waiver ....................................................      14
  Section 1.7 Conflict with Trust Indenture Act ............................................      14
  Section 1.8 Effect of Headings and Table of Contents .....................................      14
  Section 1.9 Successors and Assigns .......................................................      14
  Section 1.10 Separability Clause .........................................................      14
  Section 1.11 Benefits of Indenture .......................................................      15
  Section 1.12 Governing Law ...............................................................      15
  Section 1.13 Non-Business Days ...........................................................      15

ARTICLE II SECURITY FORMS ..................................................................      15
  Section 2.1 Forms Generally ..............................................................      15
  Section 2.2 Form of Face of Security .....................................................      16
  Section 2.3 Form of Reverse of Security ..................................................      19
  Section 2.4 Additional Provisions Required in Global Security ............................      22
  Section 2.5 Form of Trustee's Certificate of Authentication ..............................      22

ARTICLE III THE SECURITIES .................................................................      22
  Section 3.1 Title and Terms ..............................................................      22
  Section 3.2 Denominations ................................................................      25
  Section 3.3 Execution, Authentication, Delivery and Dating ...............................      25
  Section 3.4 Temporary Securities .........................................................      26
  Section 3.5 Registration, Transfer and Exchange ..........................................      27
  Section 3.6 Mutilated, Destroyed, Lost and Stolen Securities .............................      29
  Section 3.7 Payment of Interest; Interest Rights Preserved ...............................      29
  Section 3.8 Persons Deemed Owners ........................................................      31
  Section 3.9 Cancellation .................................................................      31
  Section 3.10 Computation of Interest .....................................................      31
  Section 3.11 Deferrals of Interest Payment Dates .........................................      32
  Section 3.12 Right of Set-Off ............................................................      33
  Section 3.13 Agreed Tax Treatment ........................................................      33
  Section 3.14 Shortening or Extension of Stated Maturity ..................................      33
  Section 3.15 CUSIP Numbers ...............................................................      34

ARTICLE IV SATISFACTION AND DISCHARGE ......................................................      34
  Section 4.1 Satisfaction and Discharge of Indenture ......................................      34
  Section 4.2 Application of Trust Money ...................................................      35
  Section 4.3 Satisfaction, Discharge and Defeasance of Securities of Any Series. ..........      35

ARTICLE V REMEDIES .........................................................................      39
</TABLE>

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<TABLE>
<S>                                                                                               <C>
  Section 5.1 Events of Default ............................................................      39
  Section 5.2 Acceleration of Maturity; Rescission and Annulment ...........................      40
  Section 5.3 Collection of Indebtedness and Suits for Enforcement by Trustee ..............      41
  Section 5.4 Trustee May File Proofs of Claim .............................................      42
  Section 5.5 Trustee May Enforce Claim Without Possession of Securities ...................      43
  Section 5.6 Application of Money Collected ...............................................      43
  Section 5.7 Limitation on Suits ..........................................................      43
  Section 5.8 Unconditional Right of Holders to Receive Principal, Premium and Interest;
   Direct Action by Holders of Preferred Securities ........................................      44
  Section 5.9 Restoration of Rights and Remedies ...........................................      44
  Section 5.10 Rights and Remedies Cumulative ..............................................      45
  Section 5.11 Delay or Omission Not Waiver ................................................      45
  Section 5.12 Control by Holders ..........................................................      45
  Section 5.13 Waiver of Past Defaults .....................................................      45
  Section 5.14 Undertaking for Costs .......................................................      46
  Section 5.15 Waiver of Usury, Stay or Extension Laws .....................................      46

ARTICLE VI THE TRUSTEE .....................................................................      47
  Section 6.1 Certain Duties and Responsibilities ..........................................      47
  Section 6.2 Notice of Defaults ...........................................................      48
  Section 6.3 Certain Rights of Trustee ....................................................      48
  Section 6.4 Not Responsible for Recitals or Issuance of Securities .......................      49
  Section 6.5 May Hold Securities ..........................................................      49
  Section 6.6 Money Held in Trust ..........................................................      49
  Section 6.7 Compensation and Reimbursement ...............................................      49
  Section 6.8 Disqualification; Conflicting Interests ......................................      51
  Section 6.9 Corporate Trustee Required; Eligibility ......................................      51
  Section 6.10 Resignation and Removal; Appointment of Successor ...........................      51
  Section 6.11 Acceptance of Appointment by Successor ......................................      53
  Section 6.12 Merger, Conversion, Consolidation or Succession to Business .................      53
  Section 6.13 Preferential Collection of Claims Against Company ...........................      54
  Section 6.14 Appointment of Authenticating Agent .........................................      54

ARTICLE VII HOLDER'S LISTS AND REPORTS BY TRUSTEE AND COMPANY ..............................      55
  Section 7.1 Company to Furnish Trustee Names and Addresses of Holders ....................      55
  Section 7.2 Preservation of Information, Communications to Holders .......................      56
  Section 7.3 Reports by Trustee ...........................................................      56
  Section 7.4 Reports by the Company. ......................................................      56

ARTICLE VIII CONSOLIDATION, MERGER, CONVEYANCE, TRANSFER OR LEASE ..........................      57
  Section 8.1 Company May Consolidate, Etc., Only on Certain Terms .........................      57
  Section 8.2 Successor Corporation Substituted ............................................      57

ARTICLE IX SUPPLEMENTAL INDENTURES .........................................................      58
  Section 9.1 Supplemental Indentures without Consent of Holders ...........................      58
  Section 9.2 Supplemental Indentures with Consent of Holders ..............................      59
  Section 9.3 Execution of Supplemental Indentures .........................................      61
  Section 9.4 Effect of Supplemental Indentures ............................................      61
</TABLE>

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<TABLE>
<S>                                                                                               <C>
  Section 9.5 Conformity with Trust Indenture Act ............................................    61
  Section 9.6 Reference in Securities to Supplemental Indentures .............................    61

ARTICLE X COVENANTS ..........................................................................    61
  Section 10.1 Payment of Principal, Premium and Interest ....................................    61
  Section 10.2 Maintenance of Office or Agency ...............................................    62
  Section 10.3 Money or Security Payments to be Held in Trust ................................    62
  Section 10.4 Statement as to Compliance ....................................................    63
  Section 10.5 Waiver of Certain Covenants ...................................................    64
  Section 10.6 Additional Sums ...............................................................    64
  Section 10.7 Additional Covenants ..........................................................    64

ARTICLE XI REDEMPTION OF SECURITIES ..........................................................    66
  Section 11.1 Applicability of This Article .................................................    66
  Section 11.2 Election to Redeem; Notice to Trustee .........................................    66
  Section 11.3 Selection of Securities to be Redeemed ........................................    66
  Section 11.4 Notice of Redemption ..........................................................    67
  Section 11.5 Deposit of Redemption Price ...................................................    67
  Section 11.6 Payment of Securities Called for Redemption ...................................    68
  Section 11.7 Right of Redemption of Securities Initially Issued to a ONEOK Capital Trust ...    68

ARTICLE XII SINKING FUNDS ....................................................................    69
  Section 12.1 Applicability of Article ......................................................    69
  Section 12.2 Satisfaction of Sinking Fund Payments with Securities .........................    69
  Section 12.3 Redemption of Securities for Sinking Fund .....................................    70

ARTICLE XIII SUBORDINATION OF SECURITIES .....................................................    71
  Section 13.1 Securities Subordinate to Senior Debt .........................................    71
  Section 13.2 Payment Over of Proceeds Upon Dissolution, Etc. ...............................    71
  Section 13.3 Prior Payment to Senior Debt Upon Acceleration of Securities ..................    72
  Section 13.4 No Payment When Senior Debt in Default ........................................    73
  Section 13.5 Payment Permitted If No Default ...............................................    74
  Section 13.6 Subrogation to Rights of Holders of Senior Debt ...............................    74
  Section 13.7 Provisions Solely to Define Relative Rights ...................................    74
  Section 13.8 Trustee to Effectuate Subordination ...........................................    75
  Section 13.9 No Waiver of Subordination Provisions .........................................    75
  Section 13.10 Notice to Trustee ............................................................    76
  Section 13.11 Reliance on Judicial Order or Certificate of Liquidating Agent ...............    76
  Section 13.12 Trustee Not Fiduciary for Holders of Senior Debt .............................    76
  Section 13.13 Rights of Trustee as Holder of Senior Debt; Preservation of Trustee 's
   Rights ....................................................................................    77
  Section 13.14 Article Applicable to Paying Agents ..........................................    77
  Section 13.15 Certain Conversions or Exchanges Deemed Payment ..............................    77
</TABLE>

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     JUNIOR SUBORDINATED INDENTURE dated as of [__________] (this "Indenture")
among ONEOK, INC., an Oklahoma corporation (the "Company") having its principal
office at 100 West Fifth Street, Tulsa, Oklahoma 74103, and SUNTRUST BANK, a
Georgia banking corporation with trust powers, as Trustee (hereinafter called
the "Trustee").

                             RECITALS OF THE COMPANY

     The Company has duly authorized the execution and delivery of this
Indenture (i) to provide for the issuance from time to time of its unsecured
junior subordinated notes in series (the "Securities") of substantially the
tenor hereinafter provided, including, without limitation, Securities issued to
evidence loans made to the Company of the proceeds from the issuance from time
to time by one or more statutory trusts (each, a "ONEOK Capital Trust" or "ONEOK
Trust" and, collectively, the "ONEOK Capital Trusts" or "ONEOK Trusts") of
undivided preferred trust interests in the assets of such ONEOK Capital Trusts
(the "Preferred Securities") and undivided common interests in the assets of
such ONEOK Capital Trusts (the "Common Securities" and, collectively with the
Preferred Securities, the "Trust Securities"), and (ii) to provide the terms and
conditions upon which the Securities are to be authenticated, issued and
delivered.

     All things necessary to make the Securities, when executed by the Company,
authenticated and delivered hereunder and duly issued by the Company, the valid
obligations of the Company, and to make this Indenture a valid agreement of the
Company, in accordance with their and its terms, have been done.

     NOW THEREFORE, THIS INDENTURE WITNESSETH: For and in consideration of the
premises and the purchase of the Securities by the Holders thereof, it is
mutually covenanted and agreed, for the equal and proportionate benefit of all
Holders of Securities of any series thereof, as follows:

                                   ARTICLE I

             DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION

     Section 1.1 Definitions.

     For all purposes of this Indenture (and any indenture supplemental hereto),
except as otherwise expressly provided or unless the context otherwise requires:

          (1) The terms defined in this Article have the meanings assigned to
them in this Article and include the plural as well as the singular;

          (2) All other terms used herein which are defined in the Trust
Indenture Act, either directly or by reference therein, have the meanings
assigned to them therein;

          (3) All accounting terms not otherwise defined herein or in the Trust
Indenture Act, either directly or by reference therein, have the meanings
assigned to them in accordance with generally accepted accounting principles,
and the term "generally accepted accounting principles" with respect to any
computation required or permitted hereunder shall mean such accounting
principles which are generally accepted at the date or time of such

<PAGE>

computation; provided, that when two or more principles are so generally
accepted, it shall mean that set of principles consistent with those in use by
the Company; and

          (4) The words "herein," "hereof" and "hereunder" and other words of
similar import refer to this Indenture as a whole and not to any particular
Article, Section or other subdivision.

     "Act," when used with respect to any Holder, has the meaning specified in
Section 1.4 hereof.

     "Additional Interest" means the interest, if any, that shall accrue on any
interest on the Securities of any series the payment of which has not been made
on the applicable Interest Payment Date and which shall accrue at the rate per
annum specified or determined as specified in such Security.

     "Additional Junior Indebtedness" means, without duplication and other than
the Securities, any indebtedness, liabilities, guarantees or obligations of the
Company, or any Subsidiary of the Company, under debt securities (or guarantees
in respect of debt securities, preferred securities or trust securities)
initially issued after the date of this Indenture to any trust, or a trustee of
a trust, partnership or other entity affiliated with the Company that is,
directly or indirectly, a Finance Subsidiary (as such term is defined in Rule
3a-5 under the Investment Company Act of 1940) or other financing vehicle of the
Company or any Subsidiary of the Company in connection with the issuance by that
entity of preferred securities or other securities that are issued on a pari
passu basis with the Securities.

     "Additional Sums" has the meaning specified in Section 10.6.

     "Additional Taxes" means the sum of any additional taxes, duties and other
governmental charges to which a ONEOK Capital Trust has become subject from time
to time as a result of a Tax Event.

     "Administrative Trustee" means, in respect of any ONEOK Capital Trust, each
Person identified as an "Administrative Trustee" in the related Trust Agreement,
solely in such Person's capacity as Administrative Trustee of such ONEOK Capital
Trust under such Trust Agreement and not in such Person's individual capacity,
or any successor administrative trustee appointed as therein provided.

     "Affiliate" of any specified Person means any other Person directly or
indirectly controlling or controlled by or under direct or indirect common
control with such specified Person; provided, however, no ONEOK Capital Trust to
which Securities have been issued shall be deemed to be an Affiliate of the
Company. For the purposes of this definition, "control" when used with respect
to any specified Person means the power to direct the management and policies of
such Person, directly or indirectly, whether through the ownership of voting
securities, by contract or otherwise; and the terms "controlling" and
"controlled" have meanings correlative to the foregoing.

     "Agent Member" means any member of, or participant in, the Depositary.

                                       2

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     "Allocable Amounts," when used with respect to any Senior Debt, means all
amounts due or to become due on such Senior Debt less, if applicable, any amount
which would have been paid to, and retained by, the holders of such Senior Debt
(whether as a result of the receipt of payments by the holders of such Senior
Debt from the Company or any other obligor thereon or from any holders of, or
trustee in respect of, other indebtedness that is subordinate and junior in
right of payment to such Senior Debt pursuant to any provision of such
indebtedness for the payment over of amounts received on account of such
indebtedness to the holders of such Senior Debt or otherwise) but for the fact
that such Senior Debt is subordinate or junior in right of payment to (or
subject to a requirement that amounts received on such Senior Debt be paid over
to obligees on) trade accounts payable or accrued liabilities arising in the
ordinary course of business.

     "Applicable Procedures" means, with respect to any transfer or transaction
involving a Global Security or beneficial interest therein, the rules and
procedures of the Depositary for such Global Security, in each case to the
extent applicable to such transaction and as in effect from time to time.

     "Authenticating Agent" means any Person authorized by the Trustee pursuant
to Section 6.14 to act on behalf of the Trustee to authenticate Securities of
one or more series.

     "Board of Directors" means either the board of directors of the Company or
any committee of that board duly authorized to act hereunder.

     "Board Resolution" means a copy of a resolution certified by the Secretary
or an Assistant Secretary of the Company to have been duly adopted by the Board
of Directors, or such committee of the Board of Directors or officers of the
Company to which authority to act on behalf of the Board of Directors has been
delegated, and to be in full force and effect on the date of such certification,
and delivered to the Trustee.

     "Business Day" means any day other than (i) a Saturday or Sunday, (ii) a
day on which banking institutions in The City of New York are authorized or
required by law or executive order to remain closed or (iii) a day on which the
Corporate Trust Office of the Trustee or, with respect to the Securities of a
series initially issued to a ONEOK Capital Trust, the principal office of the
Property Trustee under the related Trust Agreement, is closed for business.

     "Commission" means the Securities and Exchange Commission, as from time to
time constituted, created under the Exchange Act, or, if at any time after the
execution of this instrument such Commission is not existing and performing the
duties now assigned to it under the Trust Indenture Act, then the body
performing such duties on such date.

     "Common Securities" has the meaning specified in the first recital of this
Indenture.

     "Common Stock" means the common stock, without par value, of the Company.

     "Company" means the Person named as the "Company" in the first paragraph of
this Indenture until a successor corporation shall have become such pursuant to
the applicable provisions of this Indenture, and thereafter "Company" shall mean
any such successor corporation.

                                       3

<PAGE>

     "Company Request" and "Company Order" mean, respectively, the written
request or order signed in the name of the Company by the Chairman of the Board
of Directors, the Vice Chairman of the Board of Directors, its Chief Executive
Officer, President or a Vice President, and by its Chief Financial Officer,
Treasurer, an Assistant Treasurer, its Secretary or an Assistant Secretary, and
delivered to the Trustee.

     "Corporate Trust Office" means the principal corporate trust office of the
Trustee at which, at any particular time, its corporate trust business shall be
administered, which office at the date hereof is located at [__________], except
for purposes of Section 10.2, if required with respect to a series of
Securities, such term shall mean the office or agency of the Trustee in the
Borough of Manhattan, New York, New York which office at the date hereof is
located at [__________].

     "Corporation" includes a corporation, association, company, joint-stock
company or business trust.

     "Debt" means, with respect to any Person, whether recourse is to all or a
portion of the assets of such Person and whether or not contingent, (i) every
obligation of such Person for money borrowed; (ii) every obligation of such
Person evidenced by bonds, debentures, notes or other similar instruments,
including obligations incurred in connection with the acquisition of property,
assets or businesses; (iii) every reimbursement obligation of such Person with
respect to letters of credit, bankers' acceptances or similar facilities issued
for the account of such Person; (iv) every obligation of such Person issued or
assumed as the deferred purchase price of property or services (but excluding
trade accounts payable or accrued liabilities arising in the ordinary course of
business); (v) every capital lease obligation of such Person; (vi) all
indebtedness of such Person, whether incurred on or prior to the date of this
Indenture or thereafter incurred, for claims in respect of derivative products,
including interest rate, foreign exchange rate and commodity forward contracts,
options and swaps and similar arrangements; and (vii) every obligation of the
type referred to in clauses (i) through (vi) of another Person and all dividends
and operating lease payments of another Person the payment of which, in either
case, such Person has guaranteed or is responsible or liable for, directly or
indirectly, as obligor or otherwise.

     "Defaulted Interest" has the meaning specified in Section 3.7.

     "Depositary" means, with respect to the Securities of any series issuable
or issued in whole or in part in the form of one or more Global Securities, the
Person designated as Depositary by the Company pursuant to Section 3.1 with
respect to such series (or any successor to the Depositary).

     "Discount Security" means any security which provides for an amount less
than the principal amount thereof to be due and payable upon a declaration of
acceleration of the Maturity thereof pursuant to Section 5.2.

     "Distributions," with respect to the Trust Securities issued by a ONEOK
Capital Trust, means amounts payable in respect of such Trust Securities as
provided in the related Trust Agreement and referred to therein as
"Distributions."

                                       4

<PAGE>

         "Dollar" means the currency of the United States of America that, at
the time of payment, is legal tender for the payment of public and private
debts.

         "Event of Default," unless otherwise specified in the supplemental
indenture or Officers' Certificate creating a series of Securities, has the
meaning specified in Article V.

         "Exchange Act" means the Securities Exchange Act of 1934 and any
statute successor thereto, in each case as amended from time to time.

         "Expiration Date" has the meaning specified in Section 1.4.

         "Extension Period" has the meaning specified in Section 3.11.

         "Global Security" means a Security in the form prescribed in Section
2.4 evidencing all or part of a series of Securities, issued to the Depository
or its nominee for such series, and registered in the name of such Depository or
its nominee.

         "Government Obligations" means, unless otherwise specified with respect
to any series of Securities pursuant to Section 3.1, securities which are (i)
direct obligations of the United States government or (ii) obligations of a
Person controlled or supervised by and acting as an agency or instrumentality of
the United States government, the payment of which is unconditionally guaranteed
by the United States government, which, in either case, are full faith and
credit obligations of the United States government payable and are not callable
or redeemable at the option of the issuer thereof and shall also include a
depository receipt issued by a bank or trust company as custodian with respect
to any such Government Obligation or a specific payment of interest on or
principal of any such Government Obligation held by such custodian for the
account of the holder of a depository receipt; provided that (except as required
by law) such custodian is not authorized to make any deduction from the amount
payable to the holder of such depository receipt from any amount received by the
custodian in respect of the Government Obligation or the specific payment of
interest or principal of the Government Obligation evidenced by such depository
receipt.

         "Guarantee Agreement" means the Guarantee Agreement between the Company
and the trustee certified therein, substantially in such form as may be
specified as contemplated by Section 3.1 with respect to the Securities of any
series, in each case as amended from time to time.

         "Holder" means a Person in whose name a Security is registered in the
Securities Register.

         "Indenture" means this instrument as originally executed or as it may
from time to time be supplemented or amended by one or more indentures
supplemental hereto entered into
         pursuant to the applicable provisions hereof and shall include the
terms of each particular series of Securities established as contemplated by
Section 3.1.

         "Interest Payment Date" means, as to each series of Securities, the
Stated Maturity of an installment of interest on such Securities.

                                       5

<PAGE>
         "Investment Company Act Event" means that a ONEOK Capital Trust shall
have received an Opinion of Counsel (as defined in the relevant Trust Agreement)
experienced in such matters to the effect that, as a result of the occurrence of
a change in law or regulation or a written change in the interpretation or
application of law or regulation by any legislative body, court, governmental
agency or regulatory authority, there is more than an insubstantial risk that
such ONEOK Capital Trust is or will be considered an "investment company" that
is required to be registered under the Investment Company Act of 1940, as
amended, which change becomes effective on or after the date of issuance of the
Preferred Securities of such ONEOK Capital Trust.

         "Junior Subordinated Payment" has the meaning specified in Section
13.2.

         "Maturity," when used with respect to any Security, means the date on
which the principal of such Security becomes due and payable as therein or
herein provided, whether at the Stated Maturity or by declaration of
acceleration, call for redemption or otherwise.

         "Moody's" means Moody's Investors Service, Inc.

         "Notice of Default" means a written notice of the kind specified in
Section 5.1(3).

         "Officers' Certificate" means a certificate signed by the Chairman of
the Board of Directors, a Vice Chairman of the Board of Directors, the Chief
Executive Officer, President or a Vice President, and by the Chief Financial
Officer, Treasurer, an Assistant Treasurer, the Secretary or an Assistant
Secretary of the Company, and delivered to the Trustee. Any Officer's
Certificate delivered with respect to compliance with a condition or covenant
contained in this Indenture shall be in accordance with Section 1.2 hereof.

         "ONEOK Capital Guarantee" means the guarantee by the Company of
distributions on the Preferred Securities of a ONEOK Capital Trust to the extent
provided in the applicable Guarantee Agreement.

         "ONEOK Capital Trust" has the meaning specified in the first recital of
this Indenture.

         "Opinion of Counsel" means a written opinion of counsel, who may be
counsel for the Company and who shall be acceptable to the Trustee.

         "Original Issue Date" means the date of issuance specified as such in
each Security.

         "Outstanding" means, when used in reference to any Securities, as of
the date of determination, all Securities theretofore authenticated and
delivered under this Indenture, except:

         (i) Securities theretofore canceled by the Trustee or delivered to the
Trustee for cancellation;

         (ii) Securities for whose payment money in the necessary amount has
been theretofore deposited with the Trustee or any Paying Agent in trust for the
Holders of such Securities; and

                                       6

<PAGE>
         (iii) Securities in substitution for or in lieu of which other
Securities have been authenticated and delivered or which have been paid
pursuant to Section 3.6, unless proof satisfactory to the Trustee is presented
that any such Securities are held by Holders in whose hands such Securities are
valid, binding and legal obligations of the Company; provided, however, that in
determining whether the Holders of the requisite principal amount of Outstanding
Securities have given any request, demand, authorization, direction, notice,
consent or waiver hereunder, Securities owned by the Company or any other
obligor upon the Securities or any Affiliate of the Company or such other
obligor shall be disregarded and deemed not to be Outstanding, except that, in
determining whether the Trustee shall be protected in relying upon any such
request, demand, authorization, direction, notice, consent or waiver, only
Securities which the Trustee knows to be so owned shall be so disregarded.
Securities so owned which have been pledged in good faith may be regarded as
Outstanding if the pledgee establishes to the satisfaction of the Trustee the
pledgee's right so to act with respect to such Securities and that the pledgee
is not the Company or any other obligor upon the Securities or any Affiliate of
the Company or such other obligor (other than a ONEOK Capital Trust). Upon the
written request of the Trustee, the Company shall furnish to the Trustee
promptly an Officers' Certificate listing and identifying all Securities, if
any, known by the Company to be owned or held by or for the account of the
Company, or any other obligor on the Securities or any Affiliate of the Company
or such obligor (other than a ONEOK Capital Trust), and, subject to the
provisions of Section 6.1, the Trustee shall be entitled to accept such
Officers' Certificate as conclusive evidence of the facts therein set forth and
of the fact that all Securities not listed therein are Outstanding for the
purpose of any such determination.

         "Paying Agent" means the Trustee or any Person authorized by the
Company to pay the principal of (or premium, if any) or interest on any
Securities, or other amounts in respect of, or on behalf of the Company.

         "Person" means any individual, corporation, partnership, limited
liability company, joint venture, trust, unincorporated organization or
government or any agency or political subdivision thereof.

         "Place of Payment" means, with respect to the Securities of any series,
the place or places where the principal of (and premium, if any) and interest on
the Securities of such series are payable pursuant to Sections 3.1 and 3.11.

         "Predecessor Security" of any particular Security means every previous
Security evidencing all or a portion of the same debt as that evidenced by such
particular Security; and, for the purposes of this definition, any security
authenticated and delivered under Section 3.6 in lieu of a mutilated, lost,
destroyed or stolen Security shall be deemed to evidence the same debt as the
mutilated, lost, destroyed or stolen Security.

         "Preferred Securities" has the meaning specified in the first recital
of this Indenture.

         "Proceeding" has the meaning specified in Section 13.2.

         "Property Trustee" means, in respect of any ONEOK Capital Trust, the
commercial bank or trust company identified as the "Property Trustee" in the
related Trust Agreement, solely in its

                                       7

<PAGE>
capacity as Property Trustee of such ONEOK Capital Trust under such Trust
Agreement and not in its individual capacity, or its successor in interest in
such capacity, or any successor property trustee appointed as therein provided.

         "Redemption Date," when used with respect to any Security to be
redeemed, means the date fixed for such redemption by or pursuant to this
Indenture.

         "Redemption Price," when used with respect to any Security to be
redeemed, means the price at which it is to be redeemed pursuant to this
Indenture or the terms of such Security.

         "Regular Record Date" for the interest payable on any Interest Payment
Date with respect to the Securities of a series means, unless otherwise provided
pursuant to Section 3.1 with respect to Securities of a series, (i) in the case
of Securities of a series represented by one or more Global Securities, the
Business Day next preceding such Interest Payment Date and (ii) in the case of
Securities of a series not represented by one or more Global Securities, the
date which is fifteen days next preceding such Interest Payment Date (whether or
not a Business Day).

         "Responsible Officer," when used with respect to the Trustee, means any
officer of the Trustee assigned by the Trustee from time to time to administer
its corporate trust matters or any other officer to whom such a matter may be
referred.

         "Rights Plan" means a plan of the Company providing for the issuance by
the Company to all holders of its Common Stock of rights entitling the holders
thereof to subscribe for or purchase shares of Common Stock or any class or
series of preferred stock, which rights (i) are deemed to be transferred with
such shares of Common Stock, (ii) are not exercisable and (iii) are also issued
in respect of future issuances of Common Stock, in each case until the
occurrence of a specified event or events.

         "S&P" means Standard & Poor's Ratings Services, a division of The
McGraw-Hill Companies, Inc.

         "Securities" or "Security" means any debt securities or debt security,
as the case may be, authenticated and delivered under this Indenture.

         "Securities Register" and "Securities Registrar" have the respective
meanings specified in Section 3.5.

         "Senior Debt" means, with respect to the Company, (i) the principal,
premium, if any, and interest (including interest, whether or not allowable,
accruing after the filing of a petition initiating any proceeding under any
state, federal or foreign bankruptcy law) in respect of (A) indebtedness of the
Company and obligations related thereto and (B) indebtedness evidenced by
securities, debentures, notes, bonds or other similar instruments issued by the
Company; (ii) all capital lease, purchase money and similar obligations of the
Company; (iii) all obligations of the Company issued or assumed as the deferred
purchase price of property, all conditional sale obligations of the Company and
all obligations of the Company under any title retention agreement; (iv) all
obligations of the Company for the reimbursement of any letter of credit, any
banker's acceptance, any security purchase facility, any repurchase agreement or
similar arrangement, any commercial paper, any interest rate swap, any other
hedging arrangement, any

                                       8

<PAGE>
obligation under options or any similar credit or other transaction; (v) all
obligations for indemnification, contributions, earnouts, adjustments of
purchase price or similar obligations;(vi) all obligations in respect of workers
compensation claims, self-insurance, indemnities, bid performance, warranty
release, appeal, surety and similar bonds; (vii) all obligations of the type
referred to in clauses (i) through (vi) above of other Persons for the payment
of which the Company is responsible or liable as obligor, guarantor or
otherwise; (viii) all obligations of the type referred to in clauses (i) through
(vii) above of other Persons secured by any lien on any property or asset of the
Company (whether or not such obligation is assumed by the Company); (ix) any
other indebtedness or obligations other than those which are specifically deemed
not Senior Debt pursuant to the next sentence; and (x) all renewals, extensions,
modifications and refunding of obligations of the type referred to in clauses
(i) through (ix) above, whether incurred on or prior to the date of this
Indenture or thereafter incurred. Notwithstanding the foregoing, "Senior Debt"
shall not include (1) any Additional Junior Indebtedness, (2) Securities issued
pursuant to this Indenture and guarantees in respect of such Securities, (3)
trade accounts payable of the Company arising in the ordinary course of business
(such trade accounts payable being pari passu in right of payment to the
Securities), or (4) obligations with respect to which in the instrument creating
or evidencing the same or pursuant to which the same is outstanding, it is
provided that such obligations are pari passu or junior in right of payment to
the Securities. Senior Debt shall continue to be Senior Debt and be entitled to
the subordination provisions set forth in this Indenture irrespective of any
amendment, modification or waiver of any term of such Senior Debt.

         "Special Event" means an Investment Company Act Event or a Tax Event.

         "Special Record Date" for the payment of any Defaulted Interest means a
date fixed by the Trustee pursuant to Section 3.7.

         "Stated Maturity" when used with respect to any Security or any
installment of principal thereof or interest thereon means the date specified
pursuant to the terms of such Security as the date on which the principal of
such Security or such installment of interest is due and payable, in the case of
such principal, as such date may be shortened or extended as provided pursuant
to the terms of such Security and this Indenture.

         "Subsidiary" means, with respect to any Person, a corporation more than
50% of the outstanding voting stock of which is owned, directly or indirectly,
by such Person or by one or more other Subsidiaries, or by such Person and one
or more other Subsidiaries. For purposes of this definition, "voting stock"
means stock which ordinarily has voting power for the election of directors,
whether at all times or only so long as no senior class of stock has such voting
power by reason of any contingency.

         "Tax Event" means the receipt by a ONEOK Capital Trust of an Opinion of
Counsel (as defined in the relevant Trust Agreement) experienced in such matters
to the effect that, as a result of any amendment to, or change (including any
announced prospective change) in, the laws (or any regulations thereunder) of
the United States or any political subdivision or taxing authority thereof or
therein, or as a result of any official administrative pronouncement or judicial
decision interpreting or applying such laws or regulations, which amendment or
change is effective or which pronouncement or decision is announced on or after
the date of issuance of

                                       9

<PAGE>
the Preferred Securities of such ONEOK Capital Trust, there is more than an
insubstantial risk that (i) such ONEOK Capital Trust is, or will be within 90
days of the date of such Opinion of Counsel, subject to United States federal
income tax with respect to income received or accrued on the corresponding
series of Securities issued by the Company to such ONEOK Capital Trust, (ii)
interest payable by the Company on such corresponding series of Securities is
not, or within 90 days of the date of such Opinion of Counsel, will not be,
deductible by the Company, in whole or in part, for United States federal income
tax purposes or (iii) such ONEOK Capital Trust is, or will be within 90 days of
the date of such Opinion of Counsel, subject to more than a de minimis amount of
other taxes, duties or other governmental charges.

         "Trust Agreement" means the Trust Agreement, as amended by the form of
Amended and Restated Trust Agreement, substantially in such form as may be
specified as contemplated by Section 3.1 with respect to the Securities of any
series, in each case as amended from time to time.

         "Trustee" means the Person named as the "Trustee" in the first
paragraph of this instrument until a successor Trustee shall have become such
pursuant to the applicable provisions of this Indenture, and thereafter
"Trustee" shall mean or include each Person who is then a Trustee hereunder and,
if at any time there is more than one such Person, "Trustee," as used with
respect to the Securities of any series, shall mean the Trustee with respect to
Securities of that series.

         "Trust Indenture Act" means the Trust Indenture Act of 1939, as amended
and as in effect on the date of this Indenture, except as provided in Section
9.5.

         "Trust Securities" has the meaning specified in the first recital of
this Indenture.

         "Vice President," when used with respect to the Company or the Trustee,
as the case may be, means any duly appointed vice president, whether or not
designated by a number or a word or words added before or after the title "Vice
President."

         Section 1.2   Compliance Certificate and Opinions.

         Upon any application or request by the Company to the Trustee to take
any action under any provision of this Indenture, the Company shall furnish to
the Trustee an Officers' Certificate stating that all conditions precedent
(including covenants compliance with which constitutes a condition precedent),
if any, provided for in this Indenture relating to the proposed action have been
complied with and an Opinion of Counsel stating that in the opinion of such
counsel all such conditions precedent (including covenants compliance with which
constitutes a condition precedent), if any, have been complied with, except that
in the case of any such application or request as to which the furnishing of
such documents is specifically required by any provision of this Indenture
relating to such particular application or request, no additional certificate or
opinion need be furnished.

         Every certificate or opinion with respect to compliance with a
condition or covenant provided for in this Indenture (other than the
certificates provided pursuant to Section 10.5) shall include:

                                       10

<PAGE>
         (1) a statement that each individual signing such certificate or
opinion has read such covenant or condition and the definitions herein relating
thereto;

         (2) a brief statement as to the nature and scope of the examination or
investigation upon which the statements or opinions contained in such
certificate or opinion are based;

         (3) a statement that, in the opinion of each such individual, he has
made such examination or investigation as is necessary to enable him to express
an informed opinion as to whether or not such covenant or condition has been
complied with; and

         (4) a statement as to whether, in the opinion of each such individual,
such condition or covenant has been complied with.

         Section 1.3   Forms of Documents Delivered to Trustee.

         In any case where several matters are required to be certified by, or
covered by an opinion of, any specified Person, it is not necessary that all
such matters be certified by, or covered by the opinion of, only one such
Person, or that they be so certified or covered by only one document, but one
such Person may certify or give an opinion with respect to some matters and one
or more other such Persons may certify or give an opinion as to other matters,
and any such Person may certify or give an opinion as to such matters in one or
several documents.

         Any certificate or opinion of an officer of the Company may be based,
insofar as it relates to legal matters, upon a certificate or opinion of, or
representations by, counsel, unless such officer knows, or in the exercise of
reasonable care should know, that the certificate or opinion or representations
with respect to matters upon which his certificate or opinion is based are
erroneous. Any such certificate or Opinion of Counsel may be based, insofar as
it relates to factual matters, upon a certificate or opinion of, or
representations by, an officer or officers of the Company stating that the
information with respect to such factual matters is in the possession of the
Company, unless such counsel knows, or in the exercise of reasonable care should
know, that the certificate or opinion or representations with respect to such
matters are erroneous.

         Where any Person is required to make, give or execute two or more
applications, requests, consents, certificates, statements, opinions or other
instruments under this Indenture, they may, but need not, be consolidated and
form one instrument.

         Section 1.4   Acts of Holders.

         (a) Any request, demand, authorization, direction, notice, consent,
waiver or other action provided by this Indenture to be given to or taken by
Holders may be embodied in and evidenced by one or more instruments of
substantially similar tenor signed by such Holders in person or by an agent duly
appointed in writing; and, except as herein otherwise expressly provided, such
action shall become effective when such instrument or instruments is or are
delivered to the Trustee, and, where it is hereby expressly required, to the
Company. Such instrument or instruments (and the action embodied therein and
evidenced thereby) are herein sometimes referred to as the "Act" of the Holders
signing such instrument or instruments. Proof of execution of any such
instrument or of a writing appointing any such agent shall be sufficient

                                       11

<PAGE>

for any purpose of this Indenture and (subject to Section 6.1) conclusive in
favor of the Trustee and the Company, if made in the manner provided in this
Section.

         (b) The fact and date of the execution by any Person of any such
instrument or writing may be proved by the affidavit of a witness of such
execution or by the certificate of any notary public or other officer authorized
by law to take acknowledgments of deeds, certifying that the individual signing
such instrument or writing acknowledged to him the execution thereof. Where such
execution is by a Person acting in other than his individual capacity, such
certificate or affidavit shall also constitute sufficient proof of this
authority.

         (c) The fact and date of the execution by any Person of any such
instrument or writing, or the authority of the Person executing the same, may
also be proved in any other manner which the Trustee deems sufficient and in
accordance with such reasonable rules as the Trustee may determine.

         (d) The ownership of Securities shall be proved conclusively by the
Securities Register.

         (e) Any request, demand, authorization, direction, notice, consent,
waiver or other action by the Holder of any Security shall bind every future
Holder of the same Security and the Holder of every Security issued upon the
transfer thereof or in exchange therefor or in lieu thereof in respect of
anything done or suffered to be done by the Trustee or the Company in reliance
thereon, whether or not notation of such action is made upon such Security.

         (f) The Company may set any day as a record date for the purpose of
determining the Holders of Outstanding Securities of any series entitled to
give, make or take any request, demand, authorization, direction, notice,
consent, waiver or other action provided or permitted by this Indenture to be
given, made or taken by Holders of Securities of such series, provided that the
Company may not set a record date for, and the provisions of this paragraph
shall not apply with respect to, the giving or making of any notice,
declaration, request or direction referred to in the next paragraph. If any
record date is set pursuant to this paragraph, the Holders of Outstanding
Securities of the relevant series on such record date, and no other Holders,
shall be entitled to take the relevant action, whether or not such Holders
remain Holders after such record date, provided that no such action shall be
effective hereunder unless taken on or prior to the applicable Expiration Date
by Holders of the requisite principal amount of Outstanding Securities of such
series on such record date. Nothing in this paragraph shall be construed to
prevent the Company from setting a new record date for any action for which a
record date has previously been set pursuant to this paragraph (whereupon the
record date previously set shall automatically and with no action by any Person
be canceled and of no effect), and nothing in this paragraph shall be construed
to render ineffective any action taken by Holders of the requisite principal
amount of Outstanding Securities of the relevant series on the date such action
is taken. Promptly after any record date is set pursuant to this paragraph, the
Company, at its own expense, shall cause notice of such record date, the
proposed action by Holders and the applicable Expiration Date to be given to the
Trustee in writing and to each Holder of Securities of the relevant series in
the manner set forth in Section 1.6.

                                       12

<PAGE>
         The Trustee may set any day as a record date for the purpose of
determining the Holders of Outstanding Securities of any series entitled to join
in the giving or making of (i) any Notice of Default, (ii) any declaration of
acceleration referred to in Section 5.2, (iii) any request to institute
proceedings referred to in Section 5.7(2) or (iv) any direction referred to in
Section 5.12, in each case with respect to Securities of such series. If any
record date is set pursuant to this paragraph, the Holders of Outstanding
Securities of such series on such record date, and no other Holders, shall be
entitled to join in such notice, declaration, request or direction, whether or
not such Holders remain Holders after such record date, provided that no such
action shall be effective hereunder unless taken on or prior to the applicable
Expiration Date by Holders of the requisite principal amount of Outstanding
Securities of such series on such record date. Nothing in this paragraph shall
be construed to prevent the Trustee from setting a new record date for any
action for which a record date has previously been set pursuant to this
paragraph (whereupon the record date previously set shall automatically and with
no action by any Person be canceled and of no effect), and nothing in this
paragraph shall be construed to render ineffective any action taken by Holders
of the requisite principal amount of Outstanding Securities of the relevant
series on the date such action is taken. Promptly after any record date is set
pursuant to this paragraph, the Trustee, at the Company's expense, shall cause
notice of such record date, the proposed action by Holders and the applicable
Expiration Date to be given to the Company in writing and to each Holder of
Securities of the relevant series in the manner set forth in Section 1.6.

         With respect to any record date set pursuant to this Section, the party
hereto which sets such record date may designate any day as the "Expiration
Date" and from time to time may change the Expiration Date to any earlier or
later day, provided that no such change shall be effective unless notice of the
proposed new Expiration Date is given to the other party hereto in writing, and
to each Holder of Securities of the relevant series in the manner set forth in
Section 10.6, on or prior to the existing Expiration Date. If an Expiration Date
is not designated with respect to any record date set pursuant to this Section,
the party hereto which set such record date shall be deemed to have initially
designated the 180th day after such record date as the Expiration Date with
respect thereto, subject to its right to change the Expiration Date as provided
in this paragraph. Notwithstanding the foregoing, no Expiration Date shall be
later than the 180th day after the applicable record date.

         (g) Without limiting the foregoing, a Holder entitled hereunder to take
any action hereunder with regard to any particular Security may do so with
regard to all or any part of the principal amount of such Security or by one or
more duly appointed agents, each of which may do so pursuant to such appointment
with regard to all or any part of such principal amount.


         Section 1.5   Notices, Etc. to the Trustee and the Company

         Any request, demand, authorization, direction, notice, consent, waiver
or Act of Holders or other document provided or permitted by this Indenture to
be made upon, given or furnished to, or filed with,

         (1) the Trustee by any Holder, any holder of Preferred Securities or
the Company shall be sufficient for every purpose hereunder if made, given,
furnished or filed in writing to or with the Trustee at its Corporate Trust
Office, or

                                       13

<PAGE>
         (2) the Company by the Trustee, any Holder or any holder of Preferred
Securities shall be sufficient for every purpose (except as otherwise provided
in Section 5.1) hereunder if in writing and mailed, first class, postage
prepaid, to the Company addressed to it at the address of its principal office
specified in the first paragraph of this instrument or at any other address
previously furnished in writing to the Trustee by the Company.

         Section 1.6   Notice to Holders; Waiver.

         Where this Indenture provides for notice to Holders of any event, such
notice shall be sufficiently given (unless otherwise herein expressly provided)
if in writing and mailed, first class postage prepaid, to each Holder affected
by such event, at the address of such Holder as it appears in the Securities
Register, not later than the latest date, and not earlier than the earliest
date, prescribed for the giving of such notice. If, by reason of the suspension
or irregularities in regular mail services or for any other reason, it shall be
impossible or impracticable to mail notice of any event to Holders when said
notice is required to be given pursuant to any provision of this Indenture or of
the relevant Securities, then any manner of giving such notice as shall be
satisfactory to the Trustee shall be deemed to be a sufficient giving of such
notice. In any case where notice to Holders is given by mail, neither the
failure to mail such notice, nor any defect in any notice so mailed, to any
particular Holder shall affect the sufficiency of such notice with respect to
other Holders. Where this Indenture provides for notice in any manner, such
notice may be waived in writing by the Person entitled to receive such notice,
either before or after the event, and such waiver shall be the equivalent of
such notice. Waivers of notice by Holders shall be filed with the Trustee, but
such filing shall not be a condition precedent to the validity of any action
taken in reliance upon such waiver.

         Section 1.7   Conflict with Trust Indenture Act.

         If any provision of this Indenture limits, qualifies or conflicts with
the duties imposed by any of Sections 310 to 317, inclusive, of the Trust
Indenture Act, through operation of Section 318(c) thereof, such imposed duties
shall control. If any provisions of this Indenture modifies or exclude any
provision of the Trust Indenture Act that may be so modified or excluded, then
such provision shall be deemed to apply to this Indenture as so modified or
excluded, as the case may be.


         Section 1.8   Effect of Headings and Table of Contents.

         The Article and Section headings herein and the Table of Contents are
for convenience only and shall not affect the construction hereof.

         Section 1.9   Successors and Assigns.

         All covenants and agreements in this Indenture by the Company shall
bind each of its successors and assigns, whether so expressed or not.

         Section 1.10  Separability Clause.

                                       14

<PAGE>

     In case any provision in this Indenture or in the Securities shall be
invalid, illegal or unenforceable, the validity, legality and enforceability of
the remaining provisions shall not in any way be affected or impaired thereby.

     Section 1.11 Benefits of Indenture.

     Nothing in this Indenture or in the Securities, express or implied, shall
give to any Person, other than the parties hereto and their successors and
assigns, the holders of Senior Debt of the Company, the Holders of the
Securities and, to the extent expressly provided in Sections 5.2, 5.8, 5.9,
5.11, 5.13, 9.1 and 9.2, the holders of Preferred Securities, any benefit or any
legal or equitable right, remedy or claim under this Indenture.

     Section 1.12 Governing Law.

     This Indenture and the Securities shall be governed by and construed in
accordance with the laws of the State of New York without regard to the
principles of conflicts thereof.

     Section 1.13 Non-Business Days.

     In any case where any Interest Payment Date, Redemption Date or Stated
Maturity of any Security shall not be a Business Day, then (notwithstanding any
other provision of this Indenture or such Security) payment of interest or
principal (and premium, if any) need not be made on such date, but may be made
on the next succeeding Business Day (and no interest shall accrue for the period
from and after such Interest Payment Date, Redemption Date or Stated Maturity,
as the case may be, until such next succeeding Business Day except that, if such
Business Day is in the next succeeding calendar year, such payment shall be made
on the immediately preceding Business Day (in each case with the same force and
effect as if made on the Interest Payment Date or Redemption Date or at the
Stated Maturity).

                                   ARTICLE II

                                 SECURITY FORMS

     Section 2.1 Forms Generally.

     The Securities of each series and the Trustee's certificate of
authentication shall be in substantially the forms set forth in this Article, or
in such other form or forms as shall be established by or pursuant to a Board
Resolution and as set forth in an Officers' Certificate or in one or more
indentures supplemental hereto, in each case with such appropriate insertions,
omissions, substitutions and other variations as are required or permitted by
this Indenture and may have such letters, numbers or other marks of
identification and such legends or endorsements placed thereon as may be
required to comply with applicable tax laws or the rules of any securities
exchange or as may, consistently herewith, be determined by the officers
executing such securities, as evidenced by their execution of the Securities. If
the form of Securities of any series is established by action taken pursuant to
a Board Resolution, a copy of an appropriate record of such action shall be
certified by the Secretary or an Assistant Secretary of the Company and
delivered to the Trustee at or prior to the delivery of the Company Order
contemplated by Section 3.3 with respect to the authentication and delivery of
such Securities.

                                       15

<PAGE>

     The Trustee's certificates of authentication shall be substantially in the
form set forth in this Article.

     The definitive Securities shall be printed, lithographed or engraved or
produced by any combination of these methods, if required by any securities
exchange on which the Securities may be listed, on a steel engraved border or
steel engraved borders or may be produced in any other manner permitted by the
rules of any securities exchange on which the Securities may be listed, all as
determined by the officers executing such Securities, as evidenced by their
execution of such securities.

     Section 2.2 Form of Face of Security.

                                   ONEOK, INC.
                               (Title of Security)

No.                                                                  $__________

     ONEOK, INC., a corporation organized and existing under the laws of
Oklahoma (the "Company," which term includes any successor corporation under the
Indenture hereinafter referred to), for value received, hereby promises to pay
to _____________________, or registered assigns, the principal sum of
_______________ Dollars ($ ________) on _________ __, ____ [if applicable,
insert--;provided that the Company may (i) shorten the Stated Maturity of the
principal of this Security to a date not earlier than ___________ __, ____ and
(ii) extend the Stated Maturity of the principal of this Security at any time on
one or more occasions, subject to certain conditions specified in Section 3.14
of the Indenture, but in no event to a date later than __________]. The Company
further promises to pay interest on said principal sum from ____________ __,
____ or from the most recent interest payment date (each such date, an "Interest
Payment Date") on which interest has been paid or duly provided for, [monthly]
[quarterly] [semi-annually] [if applicable, insert--(subject to deferral as set
forth herein)] in arrears on _____________, ___________, ____________ and
___________ of each year, commencing _____________, _____________, at the rate
of ___% per annum, until the principal hereof shall have become due and payable,
[if applicable, insert--plus Additional Interest, if any,] until the principal
hereof is paid or duly provided for or made available for payment [if
applicable, insert--and on any overdue principal and (without duplication and to
the extent that payment of such interest is enforceable under applicable law) on
any overdue installment of interest at the rate of ___% per annum, compounded
[monthly] [quarterly] [semi-annually]]. The amount of interest payable for any
period shall be computed on the basis of twelve 30-day months and a 360-day
year. The amount of interest payable for any partial period shall be computed on
the basis of the number of days elapsed in a 360-day year of twelve 30-day
months. In the event that any date on which interest is payable on this Security
is not a Business Day, then a payment of the interest payable on such date will
be made on the next succeeding day which is a Business Day (and without any
interest or other payment in respect of any such delay), except that, if such
Business Day is in the next succeeding calendar year, such payment shall be made
on the immediately preceding Business Day, in each case with the same force and
effect as if made on the date the payment was originally payable. A "Business
Day" shall mean any day other than (i) a Saturday or Sunday, (ii) a day on which
banking institutions in The City of New York are authorized or required by law
or executive order to remain closed

                                       16

<PAGE>

or (iii) a day on which the Corporate Trust Office of the Trustee [if
applicable, insert--, or the principal office of the Property Trustee under the
Trust Agreement hereinafter referred to for ONEOK Capital Trust________,] is
closed for business. The interest installment so payable, and punctually paid or
duly provided for, on any Interest Payment Date will, as provided in the
Indenture, be paid to the Person in whose name this Security (or one or more
Predecessor Securities) is registered at the close of business on the Regular
Record Date for such interest installment, which shall be (i) in the case of
Securities represented by one or more Global Securities, the Business Day next
preceding such Interest Payment Date and (ii) in the case of Securities not
represented by one or more Global Securities, the date which is fifteen days
next preceding such Interest Payment Date (whether or not a Business Day). Any
such interest installment not so punctually paid or duly provided for shall
forthwith cease to be payable to the Holder on such Regular Record Date and may
either be paid to the Person in whose name this Security (or one or more
Predecessor Securities) is registered at the close of business on a Special
Record Date for the payment of such Defaulted Interest to be fixed by the
Trustee, notice whereof shall be given to Holders of Securities of this series
not less than 10 days prior to such Special Record Date, or be paid at any time
in any other lawful manner not inconsistent with the requirements of any
securities exchange on which the Securities of this series may be listed, and
upon such notice as may be required by such exchange, all as more fully provided
in said Indenture.

     [If applicable, insert--So long as no Event of Default has occurred and is
continuing, the Company shall have the right at any time during the term of this
Security to defer payment of interest on this Security, at any time or from time
to time, for up to ___ consecutive [monthly] [quarterly] [semi-annual] interest
payment periods with respect to each deferral period (each an "Extension
Period"), during which Extension Periods the Company shall have the right to
make partial payments of interest on any Interest Payment Date, and at the end
of which the Company shall pay all interest then accrued and unpaid (together
with Additional Interest thereon to the extent permitted by applicable law);
provided, however, that no Extension Period shall extend beyond the Stated
Maturity of the principal of this Security; provided, further, that during any
such Extension Period, the Company shall not, (i) declare or pay any dividends
or distributions or redeem, purchase, acquire or make a liquidation payment with
respect to, any of its capital stock or (ii) make any payment of principal of or
interest or premium, if any, on or repay, repurchase or redeem any debt security
issued by it that ranks pari passu with or junior in interest to this Security
or make any guarantee payments with respect to any guarantee by the Company of
any debt securities of any of its Subsidiaries if such guarantee ranks pari
passu with or junior in interest to this Security (other than (a) dividends or
distributions in Common Stock, (b) any declaration of a dividend in connection
with the implementation of a Rights Plan, the issuance of any Common Stock or
any class or series of preferred stock of the Company under any Rights Plan or
the repurchase of any rights distributed pursuant to a Rights Plan, and (c)
purchases of Common Stock related to the issuance of Common Stock under any of
the Company's benefit plans for their respective directors, officers or
employees). Prior to the termination of any such Extension Period, the Company
may further extend the interest payment period, provided that no Extension
Period shall ___ exceed consecutive [months] [quarters] [semi-annual periods] or
extend beyond the Stated Maturity of the principal of this Security. Upon the
termination of any such Extension Period and upon the payment of all accrued and
unpaid interest and any Additional Interest then due, the Company may elect to
begin a new Extension Period, subject to the above requirements. No interest
shall be due and payable during

                                       17

<PAGE>

an Extension Period except at the end thereof. The Company shall give the Holder
of this Security and the Trustee notice of its election to begin any Extension
Period at least one Business Day prior to the next succeeding Interest Payment
Date on which interest on this Security would be payable but for such deferral
[if applicable, insert -- or, with respect to the Securities issued to a ONEOK
Capital Trust, so long as such Securities are held by such ONEOK Capital Trust,
prior to the earlier of (i) the next succeeding date on which Distributions on
the Preferred Securities of such ONEOK Capital Trust would be payable but for
such deferral or (ii) the date the Administrative Trustee is required to give
notice to any securities exchange or other applicable self regulatory
organization or to holders of such Preferred Securities of the record date or
the date such Distributions are payable, but in any event not less than one
Business Day prior to such record date].

     Payment of the principal of (and premium, if any) and interest on this
Security will be made at the office or agency of the Company maintained for that
purpose in the United States, in such coin or currency of the United States of
America as at the time of payment is legal tender for payment of public and
private debts [if applicable, insert--; provided, however, that at the option of
the Company payment of interest may be made (i) by check mailed to the address
of the Person entitled thereto as such address shall appear in the Securities
Register or (ii) by wire transfer in immediately available funds at such place
and to such account as may be designated by the Person entitled thereto as
specified in the Securities Register].

     The indebtedness evidenced by this Security is, to the extent provided in
the Indenture, subordinate and subject in right of payments to the prior payment
in full of all Senior Debt of the Company, and this Security is issued subject
to the provisions of the Indenture with respect thereto. Each Holder of this
Security, by accepting the same, (a) agrees to and shall be bound by such
provisions, (b) authorizes and directs the Trustee on his behalf to take such
actions as may be necessary or appropriate to effectuate the subordination so
provided and (c) appoints the Trustee his attorney-in-fact for any and all such
purposes. Each Holder hereof, by his acceptance hereof, waives all notice of the
acceptance of the subordination provisions contained herein and in the Indenture
by each holder of Senior Debt of the Company, whether now outstanding or
hereafter incurred, and waives reliance by each such holder upon said
provisions.

     Reference is hereby made to the further provisions of this Security set
forth on the reverse hereof, which further provisions shall for all purposes
have the same effect as if set forth at this place.

     Unless the certificate of authentication hereon has been executed by the
Trustee referred to on the reverse hereof by manual signature, this Security
shall not be entitled to any benefit under the Indenture or be valid or
obligatory for any purpose.

     IN WITNESS WHEREOF, the Company has caused this instrument to be duly
executed.

Dated:

                                   ONEOK, INC.

                                   By:__________________________________________
                                   [President or Vice President]

                                       18

<PAGE>

Attest:

_________________________________

[Secretary or Assistant Secretary]

     SWORN TO ME and subscribed in my presence in the City of ________, State of
_____________ this __day of ________, 19___.

                                          ______________________________________
                                          Notary Public

                                          Commission Expires:___________________

                                          [NOTARIAL SEAL]

     Section 2.3 Form of Reverse of Security.

     This Security is one of a duly authorized issue of securities of the
Company (the "Securities"), issued and to be issued in one or more series under
the Junior Subordinated Indenture dated as of [__________] (the "Indenture")
between the Company and [______________________], as Trustee (herein called the
"Trustee," which term includes any successor trustee under the Indenture), to
which Indenture and all indentures supplemental thereto reference is hereby made
for a statement of the respective rights, limitations of rights, duties and
immunities thereunder of the Trustee, the Company and the Holders of the
Securities, and of the terms upon which the Securities are, and are to be,
authenticated and delivered. This Security is one of the series designated on
the face hereof [if applicable, insert--, limited in aggregate principal amount
to $___________].

     All terms used in this Security that are defined in the Indenture [if
applicable, insert -- or in the Amended and Restated Trust Agreement dated as of
____________ ____, ____, as amended (the "Trust Agreement"), for ONEOK Capital
Trust_______, among the Company, as Depositor, and the Trustees named therein,
shall have the meanings assigned to them in the Indenture [if applicable,
insert-- or the Trust Agreement, as the case may be].

     [If applicable, insert--The Company may at any time, at its option, on or
after ________, ___, and subject to the terms and conditions of Article XI of
the Indenture, redeem this Security in whole at any time or in part from time to
time, without premium or penalty, at a redemption price equal to 100% of the
principal amount thereof plus accrued and unpaid interest [if applicable,
insert--,including Additional Interest, if any,] to the Redemption Date.]

     [If applicable, insert--Upon the occurrence and during the continuation of
a Special Event in respect of a ONEOK Capital Trust, the Company may, at its
option, at any time within 90 days of the occurrence of such Special Event
redeem this Security, in whole but not in part, subject to the provisions of
Section 11.7 and the other provisions of Article XI of the Indenture, at a
redemption price equal to 100% of the principal amount thereof plus accrued and
unpaid interest, including Additional Interest, if any, to the Redemption Date.]

                                       19

<PAGE>

     In the event of redemption of this Security in part only, a new Security or
Securities of this series for the unredeemed portion hereof will be issued in
the name of the Holder hereof upon the cancellation hereof.

     The Indenture contains provisions for satisfaction and discharge of the
entire indebtedness of this Security upon compliance by the Company with certain
conditions set forth in the Indenture.

     The Indenture permits, with certain exceptions as therein provided, the
Company and the Trustee at any time to enter into a supplemental indenture or
indentures for the purpose of modifying in any manner the rights and obligations
of the Company and of the Holders of the Securities, with the consent of the
Holders of not less than a majority in principal amount of the Outstanding
Securities of each series to be affected by such supplemental indenture. The
Indenture also contains provisions permitting Holders of specified percentages
in principal amount of the Securities of each series at the time Outstanding, on
behalf of the Holders of all Securities of such series, to waive compliance by
the Company with certain provisions of the Indenture and certain past defaults
under the Indenture and their consequences. Any such consent or waiver by the
Holder of this Security shall be conclusive and binding upon such Holder and
upon all future Holders of this Security and of any Security issued upon the
registration of transfer hereof or in exchange herefor or in lieu hereof,
whether or not notation of such consent or waiver is made upon this Security.

     [If the Security is not a Discount Security,--As provided in and subject to
the provisions of the Indenture, if an Event of Default with respect to the
Securities of this series at the time Outstanding occurs and is continuing, then
and in every such case the Trustee or the Holders of not less than 25% in
principal amount of the Outstanding Securities of this series may declare the
principal amount of all the Securities of this series to be due and payable
immediately, by a notice in writing to the Company (and to the Trustee if given
by Holders), provided that, in the case of the Securities of this series issued
to a ONEOK Capital Trust, if upon an Event of Default, the Trustee or the
Holders of not less than 25% in principal amount of the Outstanding Securities
of this series fail to declare the principal of all the Securities of this
series to be immediately due and payable, the holders of at least 25% in
aggregate Liquidation Amount of the Preferred Securities then outstanding of
such ONEOK Capital Trust shall have such right by a notice in writing to the
Company and the Trustee; and upon any such declaration the principal amount of
and the accrued interest (including any Additional Interest) on all the
Securities of this series shall become immediately due and payable, provided
that the payment of principal and interest (including any Additional Interest)
on such Securities shall remain subordinated to the extent provided in Article
XIII of the Indenture.]

     [If the Security is a Discount Security,--As provided in and subject to the
provisions of the Indenture, if an Event of Default with respect to the
Securities of this series at the time Outstanding occurs and is continuing, then
and in every such case the Trustee or the Holders of not less than such portion
of the principal amount as may be specified in the terms of the Securities of
this series may declare an amount of principal of the Securities of this series
to be due and payable immediately, by a notice in writing to the Company (and to
the Trustee if given by Holders), provided that, in the case of the Securities
of this series issued to a ONEOK Capital Trust, if upon an Event of Default, the
Trustee or the Holders of not less than 25% in principal

                                       20

<PAGE>

amount of the Outstanding Securities of this series fails to declare the
principal of all the Securities of this series to be immediately due and
payable, the holders of at least 25% in aggregate Liquidation Amount of the
Preferred Securities then outstanding of such ONEOK Capital Trust shall have
such right by a notice in writing to the Company and the Trustee. The amount of
principal of the Securities of this series that may be declared due and payable
shall be equal to--insert formula for determining the amount. Upon any such
declaration, such amount of the principal of and the accrued interest (including
any Additional Interest) on all the Securities of this series shall become
immediately due and payable, provided that the payment of principal and interest
(including any Additional Interest) on such Securities shall remain subordinated
to the extent provided in Article XIII of the Indenture. Upon payment (i) of the
amount of principal so declared due and payable and (ii) of interest on any
overdue principal and overdue interest (in each case to the extent that the
payment of such interest shall be legally enforceable), all of the Company's
obligations in respect of the payment of the principal of and interest, if any,
on this Security shall terminate.]

     No reference herein to the Indenture and no provision of this Security or
of the Indenture shall alter or impair the obligation of the Company, which is
absolute and unconditional, to pay the principal of (and premium, if any) and
interest on this Security at the times, place and rate, and in the coin or
currency, herein prescribed.

     As provided in the Indenture and subject to certain limitations therein set
forth, the transfer of this Security is registerable in the Securities Register,
upon surrender of this Security for registration of transfer at the office or
agency of the Company maintained under Section 10.2 of the Indenture duly
endorsed by, or accompanied by a written instrument of transfer in form
satisfactory to the Company and the Securities Registrar duly executed by, the
Holder hereof or his attorney duly authorized in writing, and thereupon one or
more new Securities of this series, of authorized denominations and for the same
aggregate principal amount, will be issued to the designated transferee or
transferees. No service charge shall be made for any such registration of
transfer or exchange, but the Company may require payment of a sum sufficient to
cover any tax or other governmental charge payable in connection therewith.

     Prior to due presentment of this Security for registration of transfer, the
Company, the Trustee and any agent of the Company or the Trustee may treat the
Person in whose name this Security is registered as the owner hereof for all
purposes, whether or not this Security be overdue, and none of the Company, the
Trustee or any such agent shall be affected by notice to the contrary.

     The Securities of this series are issuable only in registered form without
coupons in denominations of [$25] and any integral multiple thereof. As provided
in the Indenture and subject to certain limitations therein set forth,
Securities of this series are exchangeable for a like aggregate principal amount
of Securities of such series of a different authorized denomination, as
requested by the Holder surrendering the same.

     The Company by its acceptance of this Security or a beneficial interest
therein, the Holder of, and any Person that acquires a beneficial interest in,
this Security agree that for United States federal, state and local tax purposes
it is intended that this Security constitute indebtedness.

                                       21

<PAGE>

     THE INDENTURE AND THIS SECURITY SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO CONFLICTS OF
LAWS PRINCIPLES THEREOF.

     Section 2.4 Additional Provisions Required in Global Security.

     Any Global Security issued hereunder shall, in addition to the provisions
contained in Sections 2.2 and 2.3, bear a legend in substantially the following
form:

     "This Security is a Global Security within the meaning of the Indenture
hereinafter referred to and is registered in the name of a Depositary or a
nominee of a Depositary. This Security is exchangeable for Securities registered
in the name of a person other than the Depositary or its nominee only in the
limited circumstances described in the Indenture and may not be transferred
except as a whole by the Depositary to a nominee of the Depositary or by a
nominee of the Depositary to the Depositary or another nominee of the
Depositary."

     Section 2.5 Form of Trustee's Certificate of Authentication.

     This is one of the Securities referred to in the within-mentioned
Indenture.

Dated:

_______________________________
as Trustee


_______________________________
By:
     Authorized officer

                                  ARTICLE III

                                 THE SECURITIES

     Section 3.1 Title and Terms.

     The aggregate principal amount of Securities which may be authenticated and
delivered under this Indenture is unlimited.

     The Securities may be issued in one or more series. There shall be
established in or pursuant to a Board Resolution and set forth in an Officers'
Certificate, or established in one or more indentures supplemental hereto, prior
to the issuance of Securities of a series:

     (a) the title of the Securities of such series, which shall distinguish the
Securities of the series from all other Securities;

     (b) the limit, if any, upon the aggregate principal amount of the
Securities of such series which may be authenticated and delivered under this
Indenture (except for Securities

                                       22

<PAGE>

authenticated and delivered upon registration of transfer of, or in exchange
for, or in lieu of, other Securities of the series pursuant to Section 3.4, 3.5,
3.6, 9.6 or 11.6 and except for any Securities which, pursuant to Section 3.3,
are deemed never to have been authenticated and delivered hereunder); provided,
however, that the authorized aggregate principal amount of such series may be
increased above such amount by a Board Resolution to such effect;

     (c) the Stated Maturity or Maturities on which the principal of the
Securities of such series is payable or the method of determination thereof, and
any dates on which or circumstances under which, the Company shall have the
right to extend or shorten such Stated Maturity or Maturities;

     (d) the rate or rates, if any, at which the Securities of such series shall
bear interest, if any, the rate or rates and extent to which Additional
Interest, if any, shall be payable in respect of any Securities of such series,
the date or dates from which any such Additional Interest shall accrue, the
Interest Payment Dates on which such interest shall be payable, the right,
pursuant to Section 3.11 or as otherwise set forth therein, of the Company to
defer or extend an Interest Payment Date, and the Regular Record Date for the
interest payable on any Interest Payment Date or the method by which any of the
foregoing shall be determined;

     (e) the place or places where the principal of (and premium, if any) and
interest or Additional Interest on the Securities of such series shall be
payable, the place or places where the Securities of such series may be
presented for registration of transfer or exchange, any restrictions that may be
applicable to any such transfer or exchange in addition to or in lieu of those
set forth herein, and the place or places where notices and demands to or upon
the Company in respect of the Securities of such series may be made;

     (f) any collateral, security, assurance or guarantee for a series of junior
subordinated debentures;

     (g) the period or periods within or the date or dates on which, if any, the
price or prices at which and the terms and conditions upon which the Securities
of such series may be redeemed, in whole or in part, at the option of the
Company, and, if other than by a Board Resolution, the manner in which any
election by the Company to redeem such Securities shall be evidenced;

     (h) the obligation or the right, if any, of the Company to redeem, repay or
purchase the Securities of such series pursuant to any sinking fund,
amortization or analogous provisions, and the period or periods within which,
the price or prices at which, the currency or currencies (including currency
unit or units) in which and the other terms and conditions upon which Securities
of the series shall be redeemed, repaid or purchased, in whole or in part,
pursuant to such obligation;

     (i) the denominations in which any Securities of such series shall be
issuable, if other than denominations of [$25] and any integral multiple
thereof;

     (j) if other than Dollars, the currency or currencies (including currency
unit or units) in which the principal of (and premium, if any) and interest and
Additional Interest , if any, on

                                       23

<PAGE>

the Securities of the series shall be payable, or in which the Securities of the
series shall be denominated;

     (k) the additions, modifications or deletions, if any, in the Events of
Default or covenants of the Company set forth herein with respect to the
Securities of such series;

     (l) if other than the principal amount thereof, the portion of the
principal amount of Securities of such series that shall be payable upon
declaration of acceleration of the Maturity thereof;

     (m) the additions or changes, if any, to this Indenture with respect to the
Securities of such series as shall be necessary to permit or facilitate the
issuance of the Securities of such series in bearer form, registerable or not
registerable as to principal, and with or without interest coupons;

     (n) any index or indices used to determine the amount of payments of
principal of and premium, if any, on the Securities of such series or the manner
in which such amounts will be determined;

     (o) whether the Securities of the series, or any portion thereof, shall
initially be issuable in the form of a temporary Global Security representing
all or such portion of the Securities of such series and provisions for the
exchange of such temporary Global Security for definitive Securities of such
series;

     (p) if applicable, that any Securities of the series shall be issuable in
whole or in part in the form of one or more Global Securities and, in such case,
the respective Depositaries for such Global Securities, the form of any legend
or legends which shall be borne by any such Global Security in addition to or in
lieu of that set forth in Section 2.4 and any circumstances in addition to or in
lieu of those set forth in Section 3.5 in which any such Global Security may be
exchanged in whole or in part for Securities registered, and any transfer of
such Global Security in whole or in part may be registered, in the name or names
of Persons other than the Depositary for such Global Security or a nominee
thereof;

     (q) the appointment of any Paying Agent or Agents for the Securities of
such series;

     (r) the terms of any right to convert or exchange Securities of such series
into any other securities or property of the Company, and the additions or
changes, if any, to this Indenture with respect to the Securities of such series
to permit or facilitate such conversion or exchange;

     (s) the form or forms of the Trust Agreement, Amended and Restated Trust
Agreement and Guarantee Agreement;

     (t) the relative degree, if any, to which the Securities of the series
shall be senior to or be subordinated to other series of Securities in right of
payment, whether such other series of Securities are Outstanding or not; and

                                       24

<PAGE>

         (u) any other terms of the Securities of such series (which terms shall
not be inconsistent with the provisions of this Indenture).

         All Securities of any one series shall be substantially identical
except as to denomination and except as may otherwise be provided herein or in
or pursuant to such Board Resolution and set forth in such Officers'
Certificate, or in any such indenture supplemental hereto.

         If any of the terms of the series are established by action taken
pursuant to a Board Resolution, a copy of an appropriate record of such action
shall be certified by the Secretary or an Assistant Secretary of the Company and
delivered to the Trustee at or prior to the delivery of the Officers'
Certificate of the Company setting forth the terms of the series.

         The Securities shall be subordinated in right of payment to Senior Debt
of the Company as provided in Article XIII.

         Section 3.2  Denominations.

         The Securities of each series shall be in registered form without
coupons and shall be issuable in denominations of [$25] and any integral
multiple thereof, unless otherwise specified as contemplated by Section 3.1.

         Section 3.3  Execution, Authentication, Delivery and Dating.

         The Securities shall be executed on behalf of the Company by its
President, its Chief Executive Officer or one of its Vice Presidents under its
corporate seal reproduced or impressed thereon and attested by its Secretary or
one of its Assistant Secretaries. The signature of any of these officers on the
Securities may be manual or facsimile.

         Securities bearing the manual or facsimile signatures of individuals
who were at any time the proper officers of the Company shall bind the Company,
notwithstanding that such individuals or any of them have ceased to hold such
offices prior to the authentication and delivery of such Securities or did not
hold such offices at the date of such Securities. At any time and from time to
time after the execution and delivery of this Indenture, the Company may deliver
Securities of any series executed by the Company to the Trustee for
authentication, together with a Company Order for the authentication and
delivery of such Securities, and the Trustee in accordance with the Company
Order shall authenticate and deliver such Securities. If the form or terms of
the Securities of the series have been established by or pursuant to one or more
Board Resolutions as permitted by Sections 2.1 and 3.1, in authenticating such
Securities, and accepting the additional responsibilities under this Indenture
in relation to such Securities, the Trustee shall be entitled to receive, and
(subject to Section 6.1) shall be fully protected in relying upon, an Opinion of
Counsel stating,

                  (1) if the form of such Securities has been established by or
         pursuant to Board Resolution as permitted by Section 2.1, that such
         form has been established in conformity with the provisions of this
         Indenture;

                                       25

<PAGE>
                  (2) if the terms of such Securities have been established by
         or pursuant to Board Resolution as permitted by Section 3.1, that such
         terms have been established in conformity with the provisions of this
         Indenture; and

                  (3) that such Securities, when authenticated and delivered by
         the Trustee and issued by the Company in the manner and subject to any
         conditions specified in such Opinion of Counsel, will constitute valid
         and legally binding obligations of the Company enforceable in
         accordance with their terms, subject to bankruptcy, insolvency,
         fraudulent transfer, reorganization, moratorium and similar laws of
         general applicability relating to or affecting creditors' rights and to
         general equity principles.

If such form or terms have been so established, the Trustee shall not be
required to authenticate such Securities if the issue of such Securities
pursuant to this Indenture will affect the Trustee's own rights, duties or
immunities under the Securities and this Indenture or otherwise in a manner
which is not reasonably acceptable to the Trustee.

         Notwithstanding the provisions of Section 3.1 and of the preceding
paragraph, if all Securities of a series are not to be originally issued at one
time, it shall not be necessary to deliver the Officers' Certificate of the
Company otherwise required pursuant to Section 3.1 or the Company Order and
Opinion of Counsel of the Company otherwise required pursuant to such preceding
paragraph at or prior to the authentication of each Security of such series if
such documents are delivered at or prior to the authentication upon original
issuance of the first Security of such series to be issued.

         Each Security shall be dated the date of its authentication.

         No Security shall be entitled to any benefit under this Indenture or be
valid or obligatory for any purpose, unless there appears on such Security a
certificate of authentication substantially in the form provided for herein
executed by the Trustee by the manual signature of one of its authorized
officers, and such certificate upon any Security shall be conclusive evidence,
and the only evidence, that such Security has been duly authenticated and
delivered hereunder. Notwithstanding the foregoing, if any Security shall have
been authenticated and delivered hereunder but never issued and sold by the
Company, and the Company shall deliver such Security to the Trustee for
cancellation as provided in Section 3.9, for all purposes of this Indenture such
Security shall be deemed never to have been authenticated and delivered
hereunder and shall never be entitled to the benefits of this Indenture.

         Section 3.4  Temporary Securities.

         Pending the preparation of definitive Securities of any series, the
Company may execute, and upon Company Order the Trustee shall authenticate and
deliver, temporary Securities which are printed, lithographed, typewritten,
mimeographed or otherwise produced, in any denomination, substantially of the
tenor of the definitive Securities of such series in lieu of which they are
issued and with such appropriate insertions, omissions, substitutions and other
variations as the officers executing such Securities may determine, as evidenced
by their execution of such Securities.

                                       26

<PAGE>

         If temporary Securities of any series are issued, the Company will
cause definitive Securities of such series to be prepared without unreasonable
delay. After the preparation of definitive Securities, the temporary Securities
shall be exchangeable for definitive Securities upon surrender of the temporary
Securities at the office or agency of the Company designated for that purpose
without charge to the Holder. Upon surrender for cancellation of any one or more
temporary Securities, the Company shall execute and the Trustee shall
authenticate and deliver in exchange therefor one or more definitive Securities
of the same series, of any authorized denominations having the same Original
Issue Date and Stated Maturity and having the same terms as such temporary
Securities. Until so exchanged, the temporary Securities of any series shall in
all respects be entitled to the same benefits under this Indenture as definitive
Securities of such series.

         Section 3.5  Registration, Transfer and Exchange.

         The Company shall cause to be kept at the Corporate Trust Office of the
Trustee a register in which, subject to such reasonable regulations as it may
prescribe, the Company shall provide for the registration of Securities and of
transfers of Securities. Such register is herein sometimes referred to as the
"Securities Register." The Trustee is hereby appointed "Securities Registrar"
for the purpose of registering Securities and transfers of Securities as herein
provided.

         Upon surrender for registration of transfer of any Security at the
office or agency of the Company designated for that purpose the Company shall
execute, and the Trustee shall authenticate and deliver, in the name of the
designated transferee or transferees, one or more new Securities of the same
series of any authorized denominations, of a like aggregate principal amount, of
the same Original Issue Date and Stated Maturity and having the same terms.

         At the option of the Holder, Securities may be exchanged for other
Securities of the same series of any authorized denominations, of a like
aggregate principal amount, of the same Original Issue Date and Stated Maturity
and having the same terms, upon surrender of the Securities to be exchanged at
such office or agency. Whenever any securities are so surrendered for exchange,
the Company shall execute, and the Trustee shall authenticate and deliver, the
Securities which the Holder making the exchange is entitled to receive.

         All Securities issued upon any transfer or exchange of Securities shall
be the valid obligations of the Company, evidencing the same debt, and entitled
to the same benefits under this Indenture, as the Securities surrendered upon
such transfer or exchange.

         Every Security presented or surrendered for transfer or exchange shall
(if so required by the Company or the Securities Registrar) be duly endorsed, or
be accompanied by a written instrument of transfer in form satisfactory to the
Company and the Securities Registrar, duly executed by the Holder thereof or his
attorney duly authorized in writing.

         No service charge shall be made to a Holder for any transfer or
exchange of Securities, but the Company may require payment of a sum sufficient
to cover any tax or other governmental charge that may be imposed in connection
with any transfer or exchange of Securities.

                                       27

<PAGE>

         The provisions of Clauses (1), (2), (3), (4), (5) and (6) below shall
apply only to Global Securities:

                  (1) Each Global Security authenticated under this Indenture
         shall be registered in the name of the Depositary designated for such
         Global Security or a nominee thereof and delivered to such Depositary
         or a nominee thereof or custodian therefor, and each such Global
         Security shall constitute a single Security for all purposes of this
         Indenture.

                  (2) Notwithstanding any other provision in this Indenture, no
         Global Security may be exchanged in whole or in part for Securities
         registered, and no transfer of a Global Security in whole or in part
         may be registered, in the name of any Person other than the Depositary
         for such Global Security or a nominee thereof unless (A) such
         Depositary (i) has notified the Company that it is unwilling or unable
         to continue as Depositary for such Global Security or (ii) has ceased
         to be a clearing agency registered under the Exchange Act at a time
         when the Depositary is required to be so registered to act as
         depositary, in each case unless the Company has approved a successor
         Depositary within 90 days, (B) there shall have occurred and be
         continuing an Event of Default with respect to such Global Security,
         (C) the Company in its sole discretion determines that such Global
         Security will be so exchangeable or transferable or (D) there shall
         exist such circumstances, if any, in addition to or in lieu of the
         foregoing as have been specified for this purpose as contemplated by
         Section 3.1.

                  (3) Subject to Clause (2) above, any exchange of a Global
         Security for other Securities may be made in whole or in part, and all
         Securities issued in exchange for a Global Security or any portion
         thereof shall be registered in such names as the Depositary for such
         Global Security shall direct.

                  (4) Every Security authenticated and delivered upon
         registration of transfer of, or in exchange for or in lieu of, a Global
         Security or any portion thereof, whether pursuant to this Section,
         Section 3.4, 3.6, 9.6 or 11.6 or otherwise, shall be authenticated and
         delivered in the form of, and shall be, a Global Security, unless such
         Security is registered in the name of a Person other than the
         Depositary for such Global Security or a nominee thereof.

                  (5) The Depositary or its nominee, as the registered owner of
         a Global Security, shall be the Holder of such Global Security for all
         purposes under this Indenture and the Securities, and owners of
         beneficial interests in a Global Security shall hold such interests
         pursuant to the Applicable Procedures. Accordingly, any such owner's
         beneficial interest in a Global Security shall be shown only on, and
         the transfer of such interest shall be effected only through, records
         maintained by the Depositary or its nominee or agent. Neither the
         Trustee nor the Securities Registrar shall have any liability in
         respect of any transfers effected by the Depositary.

                  (6) The rights of owners of beneficial interests in a Global
         Security shall be exercised only through the Depositary and shall be
         limited to those established by law and agreements between such owners
         and the Depositary and/or its Agent Members.

                                       28

<PAGE>

         Neither the Company nor the Trustee shall be required, pursuant to the
provisions of this Section, (a) to issue, register the transfer of or exchange
any Security of any series during a period beginning at the opening of business
15 days before the day of selection for redemption of Securities pursuant to
Article XI and ending at the close of business on the day of mailing of notice
of redemption or (b) register the transfer or exchange any Security so selected
for redemption in whole or in part, except, in the case of any Security to be
redeemed in part, any portion thereof not to be redeemed.

         Section 3.6  Mutilated, Destroyed, Lost and Stolen Securities.

         If any mutilated Security is surrendered to the Trustee together with
such security or indemnity, and/or other assurance as may be required by the
Company or the Trustee, in their discretion, to save each of them harmless, the
Company shall execute and the Trustee shall authenticate and deliver in exchange
therefor a new Security of the same issue and series of like tenor and principal
amount, having the same Original Issue Date and Stated Maturity, and bearing a
number not contemporaneously outstanding.

         If there shall be delivered to the Company and to the Trustee (i)
evidence to their satisfaction of the destruction, loss or theft of any
Security, and (ii) such security or indemnity and/or other assurance as may be
required by them to save each of them harmless, then, in the absence of notice
to the Company, or the Trustee that such Security has been acquired by a bona
fide purchaser, the Company shall execute and, upon the Company's request, the
Trustee shall authenticate and deliver, in lieu of any such destroyed, lost or
stolen Security, a new Security of the same issue and series of like tenor and
principal amount, having the same Original Issue Date and Stated Maturity as
such destroyed, lost or stolen Security, and bearing a number not
contemporaneously outstanding.

         In case any such mutilated, destroyed, lost or stolen Security has
become or is about to become due and payable, the Company in its discretion may,
instead of issuing a new Security, pay such Security.

         Upon the issuance of any new Security under this Section, the Company
may require the payment of a sum sufficient to cover any tax or other
governmental charge that may be imposed in relation thereto and any other
expenses (including the fees and expenses of the Trustee) connected therewith.

         Every new Security issued pursuant to this Section in lieu of any
destroyed, lost or stolen Security shall constitute an original additional
contractual obligation of the Company, whether or not the destroyed, lost or
stolen Security shall be at any time enforceable by anyone, and shall be
entitled to all the benefits of this Indenture equally and proportionately with
any and all other Securities duly issued hereunder.

         The provisions of this Section are exclusive and shall preclude (to the
extent lawful) all other rights and remedies with respect to the replacement or
payment of mutilated, destroyed, lost or stolen Securities.

         Section 3.7  Payment of Interest and Additional Interest; Interest
Rights Preserved.

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<PAGE>

         Interest and Additional Interest on any Security of any series which is
due and payable, and is punctually paid or duly provided for, on any Interest
Payment Date, shall be paid to the Person in whose name that Security (or one or
more Predecessor Securities) is registered at the close of business on the
Regular Record Date for such interest in respect of Securities of such series,
except that, unless otherwise provided in the Securities of such series,
interest payable on the Stated Maturity of the principal of a Security shall be
paid to the Person to whom principal is paid. The initial payment of interest on
any Security of any series which is issued between a Regular Record Date and the
related Interest Payment Date shall be payable as provided in such Security or
in the Board Resolution pursuant to Section 3.1 with respect to the related
series of Securities.

         Any interest on any Security which is due and payable, but is not
timely paid or duly provided for, on any Interest Payment Date for Securities of
such series (herein called "Defaulted Interest"), shall forthwith cease to be
payable to the registered Holder on the relevant Regular Record Date by virtue
of having been such Holder, and such Defaulted Interest may be paid by the
Company, at its election in each case, as provided in Clause (1) or (2) below:

         (1) The Company may elect to make payment of any Defaulted Interest to
the Persons in whose names the Securities of such series in respect of which
interest is in default (or their respective Predecessor Securities) are
registered at the close of business on a Special Record Date for the payment of
such Defaulted Interest, which shall be fixed in the following manner. The
Company shall notify the Trustee in writing of the amount of Defaulted Interest
proposed to be paid on each Security and the date of the proposed payment, and
at the same time the Company shall deposit with the Trustee an amount of money
equal to the aggregate amount proposed to be paid in respect of such Defaulted
Interest or shall make arrangements satisfactory to the Trustee for such deposit
prior to the date of the proposed payment, such money when deposited to be held
in trust for the benefit of the Persons entitled to such Defaulted Interest as
in this Clause provided. Thereupon the Trustee shall fix a Special Record Date
for the payment of such Defaulted Interest which shall be not more than 15 days
and not less than 10 days prior to the date of the proposed payment and not less
than 10 days after the receipt by the Trustee of the notice of the proposed
payment. The Trustee shall promptly notify the Company of such Special Record
Date and, in the name and at the expense of the Company, shall cause notice of
the proposed payment of such Defaulted Interest and the Special Record Date
therefor to be mailed, first class, postage prepaid, to each Holder of a
Security of such series at the address of such Holder as it appears in the
Securities Register not less than 10 days prior to such Special Record Date. The
Trustee may, in its discretion, in the name and at the expense of the Company,
cause a similar notice to be published at least once in a newspaper, customarily
published in the English language on each Business Day and of general
circulation in the Borough of Manhattan, The City of New York, but such
publication shall not be a condition precedent to the establishment of such
Special Record Date. Notice of the proposed payment of such Defaulted Interest
and the Special Record Date therefor having been mailed as aforesaid, such
Defaulted Interest shall be paid to the Persons in whose names the Securities of
such series (or their respective Predecessor Securities) are registered on such
Special Record Date and shall no longer be payable pursuant to the following
Clause (2).

         (2) The Company may make payment of any Defaulted Interest in any other
lawful manner not inconsistent with the requirements of any securities exchange
on which the Securities

                                       30

<PAGE>

of the series in respect of which interest is in default may be listed and, upon
such notice as may be required by such exchange (or by the Trustee if the
Securities are not listed), if after notice given by the Company to the Trustee
of the proposed payment pursuant to this Clause, such payment shall be deemed
practicable by the Trustee.

         Subject to the foregoing provisions of this Section, each Security
delivered under this Indenture upon transfer of or in exchange for or in lieu of
any other Security shall carry the rights to interest accrued and unpaid, and to
accrue interest, which were carried by such other Security.

         No Holder of any beneficial interest in any Global Security held on its
behalf by a Depositary shall have any rights under this Indenture with respect
to such Global Security, and such Depositary may be treated by the Company, the
Trustee and any agent of the Company or the Trustee as the owner of such Global
Security for all purposes whatsoever. Notwithstanding the foregoing, nothing
herein shall prevent the Company, the Trustee or any agent of the Company or the
Trustee from giving effect to any written certification, proxy or other
authorization furnished by a Depositary or impair, as between a Depositary and
such Holders of beneficial interests, the operation of customary practices
governing the exercise of the rights of the Depositary (or its nominee) as
Holder of any Security.

         Section 3.8  Persons Deemed Owners.

         The Company, the Trustee and any agent of the Company or the Trustee
may treat the Person in whose name any Security is registered as the owner of
such Security for the purpose of receiving payment of principal of and (subject
to Section 3.7) any interest on such Security and for all other purposes
whatsoever, whether or not such Security be overdue, and none of the Company,
the Trustee or any agent of the Company or the Trustee shall be affected by
notice to the contrary.

         Section 3.9  Cancellation.

         All Securities surrendered for payment, redemption, transfer or
exchange shall, if surrendered to any Person other than the Trustee, be
delivered to the Trustee, and any such Securities and Securities surrendered
directly to the Trustee for any such purpose shall be promptly canceled by it.
The Company may at any time deliver to the Trustee for cancellation any
Securities previously authenticated and delivered hereunder which the Company
may have acquired in any manner whatsoever, and all Securities so delivered
shall be promptly canceled by the Trustee. No Securities shall be authenticated
in lieu of or in exchange for any Securities canceled as provided in this
Section, except as expressly permitted by this Indenture. All canceled
Securities shall be destroyed by the Trustee and the Trustee shall, if
requested, deliver to the Company a certificate of such destruction.

         Section 3.10 Computation of Interest.

         Except as otherwise specified as contemplated by Section 3.1 for
Securities of any series, interest on the Securities of each series for any
period shall be computed on the basis of a 360-day year of twelve 30-day months
and interest on the Securities of each series for any partial period shall be
computed on the basis of the number of days elapsed in a 360-day year of twelve
30-day months.

                                       31

<PAGE>

         Section 3.11 Deferrals of Interest Payment Dates.

         If specified as contemplated by Section 2.1 or Section 3.1 with respect
to the Securities of a particular series, so long as no Event of Default has
occurred and is continuing, the Company shall have the right, at any time during
the term of such series, from time to time to defer the payment of interest on
such Securities for such period or periods as may be specified as contemplated
by Section 3.1 (each, an "Extension Period") [not to exceed the number of
consecutive [quarterly, semi-annual or other periods] that equal years with
respect to each Extension Period, during which Extension Periods the Company
shall have the right to make no payments or partial payments of interest on any
Interest Payment Date. No Extension Period shall end on a date other than an
Interest Payment Date. At the end of any such Extension Period, the Company
shall pay all interest then accrued and unpaid on the Securities (together with
Additional Interest thereon, if any, at the rate specified for the Securities of
such series to the extent permitted by applicable law); provided, however, that
no Extension Period shall extend beyond the Stated Maturity of the principal of
the Securities of such series; provided, further, that during any such Extension
Period, the Company shall not, (i) declare or pay any dividends or distributions
on, or redeem, purchase, acquire or make a liquidation payment with respect to,
any of its capital stock, or (ii) make any payment of principal of or interest
or premium, if any, on or repay, repurchase or redeem any debt security issued
by it that ranks pari passu with or junior in interest to the Securities of such
series or make any guarantee payments with respect to any guarantee by the
Company of the debt securities of any of its Subsidiaries that by their terms
rank pari passu with or junior in interest to the securities of such series
(other than (a) repurchases, redemptions or other acquisitions of shares of
capital stock of the Company in connection with any employment contract, benefit
plan or other similar arrangement with or for the benefit of any one or more
employees, officers, directors or consultants, in connection with a dividend
reinvestment or stockholder stock purchase plan or in connection with the
issuance of capital stock of the Company (or securities convertible into or
exercisable for such capital stock) as consideration in an acquisition
transaction entered into prior to the applicable Extension Period, (b) as a
result of an exchange or conversion of any class or series of the Company's
capital stock (or any capital stock of a Subsidiary of the Company) for any
class or series of the Company's capital stock or of any class or series of the
Company's indebtedness for any class or series of the Company's capital stock,
(c) the purchase of fractional interests in shares of the Company's capital
stock pursuant to the conversion or exchange provisions of such capital stock or
the security being converted or exchanged, (d) any declaration of a dividend in
connection with any Rights Plan, or the issuance of rights, stock or other
property under any Rights Plan, or the redemption or repurchase of rights
pursuant thereto, or (e) any dividend in the form of stock, warrants, options or
other rights where the dividend stock or the stock issuable upon exercise of
such warrants, options or other rights is the same stock as that on which the
dividend is being paid or ranks pari passu with or junior to such stock). Prior
to the termination of any such Extension Period, the Company may further extend
the interest payment period, provided that no Extension Period shall exceed the
period or periods specified in such Securities or extend beyond the Stated
Maturity of the principal of such Securities. Upon termination of any Extension
Period and upon the payment of all accrued and unpaid interest and any
Additional Interest then due on any Interest Payment Date, the Company may elect
to begin a new Extension Period, subject to the above requirements. No interest
shall be due and payable during an Extension Period, except at the end thereof.
The Company shall give the Holders of the Securities of such series and the
Trustee notice of its election to begin or extend any such

                                       32

<PAGE>

Extension Period at least one Business Day prior to the next succeeding Interest
Payment Date on which interest on Securities of such series would be payable but
for such deferral or, with respect to the Securities of a series issued to a
ONEOK Capital Trust, so long as such Securities are held by such ONEOK Capital
Trust, prior to the earlier of (i) the next succeeding date on which
Distributions on the Preferred Securities of such ONEOK Capital Trust would be
payable but for such deferral or (ii) the date the Administrative Trustee of
such ONEOK Capital Trust are required to give notice to any securities exchange
or other applicable self regulatory organization or to holders of such Preferred
Securities of the record date or the date such Distributions are payable, but in
any event not less than one Business Day prior to such record date.

         The Trustee shall promptly give notice of the Company's election to
begin any such Extension Period to the Holders of the Outstanding Securities of
such series.

         Section 3.12  Right of Set-Off.

         With respect to the Securities of a series issued to a ONEOK Capital
Trust, notwithstanding anything to the contrary in this Indenture, the Company
shall have the right to set-off any payment it is otherwise required to make in
respect of any such Security to the extent the Company has theretofore made, or
is concurrently on the date of such payment making, a payment with respect to
the ONEOK Capital Guarantee relating to such Security, or the Company has
theretofore made, or is concurrently on the date of such payment making, a
payment under Section 5.8 of this Indenture.

         Section 3.13  Agreed Tax Treatment.

         Each Security issued hereunder shall provide that the Company and, by
its acceptance of a Security or a beneficial interest therein, the Holder of,
and any Person that acquires a beneficial interest in, such Security agree that
for United States federal, state and local tax purposes it is intended that such
Security constitute indebtedness.

         Section 3.14  Shortening or Extension of Stated Maturity.

         If specified as contemplated by Section 2.1 or Section 3.1 with respect
to the Securities of a particular series, the Company shall have the right to
(i) shorten the Stated Maturity of the principal of the Securities of such
series at any time to any date not earlier than the first date on which the
Company has the right to redeem the Securities of such series, and (ii) extend
the Stated Maturity of the principal of the Securities of such series at any
time at its election for one or more periods, but in no event to a date later
than the [49th] anniversary of the first Interest Payment Date following the
Original Issue Date of the Securities of such series; provided that, if the
Company elects to exercise its right to extend the Stated Maturity of the
principal of the Securities of such series pursuant to clause (ii), above, at
the time such election is made and at the time of extension (A) the Company is
not in bankruptcy, otherwise insolvent or in liquidation, (B) the Company is not
in default in the payment of any interest or principal on such Securities, (C)
in the case of any series of Securities issued to a ONEOK Capital Trust, such
ONEOK Capital Trust is not in arrears on payments of Distributions on the
Preferred Securities issued by such ONEOK Capital Trust and no deferred
Distributions are accumulated and (D) such Securities are rated not less than
BBB- by S&P or Baa3 by Moody's, or the equivalent by

                                       33

<PAGE>

any other nationally recognized statistical orating organization. In the event
the Company elects to shorten or extend the Stated Maturity of the Securities of
a particular series, it shall give notice to the Trustee, no less than 30 and no
more than 60 days prior to the effectiveness thereof. The Trustee shall give
notice of such shortening or extension to the Holders promptly upon receipt.

         Section 3.15  CUSIP Numbers.

         The Company in issuing the Securities may use "CUSIP" numbers (if then
generally in use), and, if so, the Trustee shall use "CUSIP" numbers in notices
of redemption as a convenience to Holders; provided that any such notice may
state that no representation is made as to the correctness of such numbers
either as printed on the Securities or as contained in any notice of a
redemption and that reliance may be placed only on the other identification
numbers printed on the Securities, and any such redemption shall not be affected
by any defect in or omission of such "CUSIP" numbers.

                                   ARTICLE IV

                           SATISFACTION AND DISCHARGE

         Section 4.1   Satisfaction and Discharge of Indenture.

         This Indenture shall, upon Company Request, cease to be of further
effect (except as to any surviving rights of registration of transfer or
exchange of Securities herein expressly provided for and as otherwise provided
in this Section 4.1) and the Trustee, on demand of and at the expense of the
Company, shall execute proper instruments acknowledging satisfaction and
discharge of this Indenture, when

         (1) either

         (A) all Securities theretofore authenticated and delivered (other than
(i) Securities which have been destroyed, lost or stolen and which have been
replaced or paid as provided in Section 3.6 and (ii) Securities for whose
payment money has theretofore been deposited in trust or segregated and held in
trust by the Company and thereafter repaid to the Company or discharged from
such trust, as provided in Section 10.3) have been delivered to the Trustee for
cancellation; or

         (B) all such Securities not theretofore delivered to the Trustee for
cancellation

            (i)   have become due and payable, or

            (ii)  will become due and payable at their Stated Maturity within
                  one year of the date of deposit, or

            (iii) are to be called for redemption within one year under
                  arrangements satisfactory to the Trustee for the giving of
                  notice of redemption by the Trustee in the name, and at the
                  expense, of the Company,

                                       34

<PAGE>

         and the Company, in the case of Clause (B) (i), (ii) or (iii) above,
         has deposited or caused to be deposited with the Trustee as trust funds
         in trust for such purpose an amount in the currency or currencies in
         which the Securities of such series are payable sufficient to pay and
         discharge the entire indebtedness on such Securities not theretofore
         delivered to the Trustee for cancellation, for principal (and premium,
         if any) and interest (including any Additional Interest) to the date of
         such deposit (in the case of Securities which have become due and
         payable) or to the Stated Maturity or Redemption Date, as the case may
         be; and

     (2) the Company has paid or caused to be paid all other sums payable
hereunder by the Company; and


     (3) the Company has delivered to the Trustee an Officers' Certificate and
an Opinion of Counsel each stating that all conditions precedent herein provided
for relating to the satisfaction and discharge of this Indenture have been
complied with.

Notwithstanding the satisfaction and discharge of this Indenture, the
obligations of the Company to the Trustee under Section 6.7, the obligations of
the Trustee to any Authenticating Agent under Section 6.14 and, if money shall
have been deposited with the Trustee pursuant to subclause (B) of clause (1) of
this Section, the obligations of the Trustee under Section 4.2 and the last
paragraph of Section 10.3 shall survive.

     Section 4.2 Application of Trust Money.

     Subject to the provisions of the last paragraph of Section 10.3, all money
deposited with the Trustee pursuant to Section 4.1 shall be held in trust and
applied by the Trustee, in accordance with the provisions of the Securities and
this Indenture, to the payment, either directly or through any Paying Agent
(including the Company acting as its own Paying Agent) as the Trustee may
determine, to the Persons entitled thereto, of the principal (and premium, if
any) and interest (including any Additional Interest) for the payment of which
such money or obligations have been deposited with or received by the Trustee.

     Section 4.3 Company's Option to Effect Defeasance or Covenant Defeasance.

     Except as otherwise specified as contemplated by Section 3.1 for Securities
of any series, the provisions of this Article IV shall apply to each series of
Securities, and the Company may, at its option, effect defeasance of the
Securities of or within a series under Section 4.4, or covenant defeasance of
the Securities of or within a series under Section 4.5 in accordance with the
terms of such Securities and in accordance with this Article.

     Section 4.4 Defeasance and Discharge.

     Upon the Company's exercise of the above option applicable to this Section
with respect to any Securities of or within a series, the Company shall be
deemed to have been discharged from its obligations with respect to such
Outstanding Securities on the date the conditions set forth in Section 4.6 are
satisfied (hereinafter, "defeasance"). For this purpose,

                                       35

<PAGE>

such defeasance means that the Company shall be deemed to have paid and
discharged the entire indebtedness represented by such Outstanding Securities,
which shall thereafter be deemed to be "Outstanding" only for the purposes of
Section 4.7 and the other Sections of this Indenture referred to in (A) and (B)
below, and to have satisfied all its other obligations under such Securities and
this Indenture insofar as such Securities are concerned (and the Trustee, at the
expense of the Company, shall execute proper instruments acknowledging the
same), except for the following which shall survive until otherwise terminated
or discharged hereunder: (A) the rights of Holders of such Outstanding
Securities to receive, solely from the trust fund described in Section 4.6 and
as more fully set forth in such Section, payments in respect of the principal of
(and premium, if any) and interest, if any, on such Securities when such
payments are due, (B) the Company's obligations with respect to such Securities
under Sections 3.4, 3.5, 3.6, 10.2 and 10.3 and with respect to the payment of
Additional Sums, if any, on such Securities as contemplated by Section 10.6, (C)
the rights, powers, trusts, duties and immunities of the Trustee hereunder and
(D) this Article IV. Subject to compliance with this Article IV, the Company may
exercise its option under this Section 4.4 notwithstanding the prior exercise of
its option under Section 4.5 with respect to such Securities. Money and
securities held in trust pursuant to this Section 4.4 shall not be subject to
Aritlce XIII.

     Section 4.5 Covenant Defeasance.

         Upon the Company's exercise under Section 4.3 of the option applicable
to this Section 4.5 with respect to any Securities of or within a series, if
specified pursuant to Section 3.1, the Company shall be released from its
obligations under any other covenant, with respect to such Outstanding
Securities on and after the date the conditions set forth in Section 4.6 are
satisfied (hereinafter, "covenant defeasance"), and such Securities shall
thereafter be deemed to be not "Outstanding" for the purposes of any direction,
waiver, consent or declaration or Act of Holders (and the consequences of any
thereof) in connection with such covenants, but shall continue to be deemed
"Outstanding" for all other purposes hereunder (it being understood that such
Securities shall not be deemed Outstanding for financial accounting purposes).
For this purpose, such covenant defeasance means that, with respect to such
Outstanding Securities, the Company may omit to comply with and shall have no
liability in respect of any term, condition or limitation set forth in any such
covenant, whether directly or indirectly, by reason of any reference elsewhere
herein to any such covenant or by reason of reference in any such covenant to
any other provision herein or in any other document and such omission to comply
shall not constitute a default or an Event of Default under Section 5.1(3) or
Section 5.1(6) or otherwise, as the case may be, but, except as specified above,
the remainder of this Indenture and such Securities shall be unaffected thereby.

     Section 4.6 Conditions to Defeasance or Covenant Defeasance.

         The following shall be the conditions to application of either Section
4.4 or Section 4.5 to any Outstanding Securities of or within a series:

     (a) The Company shall irrevocably have deposited or caused to be deposited
with the Trustee (or another trustee satisfying the requirements of Section 6.9
who shall agree to comply with the provisions of this Article IV applicable to
it) as trust funds in trust for the purpose of making the following payments,
specifically pledged as security for, and dedicated solely to, the

                                       36

<PAGE>

benefit of the Holders of such Securities, (A) an amount or (B) Government
Obligations applicable to such Securities which through the scheduled payment of
principal and interest in respect thereof in accordance with their terms will
provide, not later than one day before the due date of any payment of principal
of and premium, if any, and interest, if any, under such Securities money in an
amount, or (C) a combination thereof, sufficient, in the opinion of a nationally
recognized firm of independent public accountants expressed in a written
certification thereof delivered to the Trustee, to pay and discharge, and which
shall be applied by the Trustee (or other qualifying trustee) to pay and
discharge, (i) the principal of (and premium, if any) and interest, if any, on
such Outstanding Securities on the Stated Maturity (or Redemption Date, if
applicable) of such principal (and premium, if any) or installment of interest,
if any, and (ii) any mandatory sinking fund payments or analogous payments
applicable to such Outstanding Securities on the day on which such payments are
due and payable in accordance with the terms of this Indenture and of such
Securities; provided that the Trustee shall have been irrevocably instructed to
apply such money or the proceeds of such Government Obligations to said payments
with respect to such Securities. Before such a deposit, the Company may give to
the Trustee, in accordance with Section 11.2 hereof, a notice of its election to
redeem all or any portion of such Outstanding Securities at a future date in
accordance with the terms of the Securities of such series and Article XI
hereof, which notice shall be irrevocable. Such irrevocable redemption notice,
if given, shall be given effect in applying the foregoing.

     (b) No default or Event of Default with respect to such Securities shall
have occurred and be continuing on the date of such deposit or, insofar as
paragraphs (4) and (5) of Section 5.1 are concerned, at any time during the
period ending on the 91st day after the date of such deposit (it being
understood that this condition shall not be deemed satisfied until the
expiration of such period).

     (c) No event or condition shall exist that would prevent the Company from
making payments of the principal of (and premium, if any) or interest on the
Securities on the date of such deposit or at any time during the period ending
on the 91st day after the date of such deposit (it being understood that this
condition shall not be deemed satisfied until the expiration of such period).

     (d) Such defeasance or covenant defeasance shall not result in a breach or
violation of, or constitute a default under, this Indenture or any other
material agreement or instrument to which the Company is a party or by which it
is bound.

     (e) In the case of an election under Section 4.4, the Company shall have
delivered to the Trustee an Opinion of Counsel stating that (x) the Company has
received from, or there has been published by, the Internal Revenue Service a
ruling, or (y) since the date of execution of this Indenture, there has been a
change in the applicable federal income tax law, in either case to the effect
that, and based thereon such opinion shall confirm that, the Holders of such
Outstanding Securities will not recognize income, gain or loss for federal
income tax purposes as a result of such defeasance and will be subject to
federal income tax on the same amounts, in the same manner and at the same times
as would have been the case if such defeasance had not occurred.

                                       37

<PAGE>

     (f) In the case of an election under Section 4.5, the Company shall have
delivered to the Trustee an Opinion of Counsel to the effect that the Holders of
such Outstanding Securities will not recognize income, gain or loss for federal
income tax purposes as a result of such covenant defeasance and will be subject
to federal income tax on the same amounts, in the same manner and at the same
times as would have been the case if such covenant defeasance had not occurred.

     (g) In the case of an election under either Section 4.4 or 4.5, the Company
shall represent to the Trustee that the deposit made by the Company pursuant to
its election under Section 4.4 or 4.5 was not made by the Company with the
intent of preferring the Holders of Securities of any series over other
creditors of the Company or with the intent of defeating, hindering, delaying or
defrauding creditors of the Company or others.

     (h) Notwithstanding any other provisions of this Section, such defeasance
or covenant defeasance shall be effected in compliance with any additional or
substitute terms, conditions or limitations in connection therewith pursuant to
Section 3.1.

     (i) The Company shall have delivered to the Trustee an Officers'
Certificate and an Opinion of Counsel, each stating that all conditions
precedent provided for relating to either the defeasance under Section 4.4 or
the covenant defeasance under Section 4.5 (as the case may be) have been
complied with.

     Section 4.7 Deposited Money and Government Obligations to Be Held in Trust;
Other Miscellaneous Provisions.

         Subject to the provisions of the last paragraph of Section 10.3, all
money and Government Obligations (or other property as may be provided pursuant
to Section 3.1) (including the proceeds thereof) deposited with the Trustee (or
other qualifying trustee, collectively for purposes of this Section 4.7, the
"Trustee") pursuant to Section 4.6 in respect of such Outstanding Securities
shall be held in trust and applied by the Trustee, in accordance with the
provisions of such Securities and this Indenture, to the payment, either
directly or through any Paying Agent (including the Company acting as its own
Paying Agent) as the Trustee may determine, to the Holders of such Securities of
all sums due and to become due thereon in respect of principal (and premium, if
any) and interest, if any, but such money need not be segregated from other
funds except to the extent required by law.

         The Company shall pay and indemnify the Trustee against any tax, fee or
other charge imposed on or assessed against the Government Obligations deposited
pursuant to Section 4.6 or the principal and interest received in respect
thereof other than any such tax, fee or other charge which by law is for the
account of the Holders of such Outstanding Securities.

         Anything in this Article IV to the contrary notwithstanding, the
Trustee shall deliver or pay to the Company from time to time upon Company
Request any money or Government Obligations (or other property and any proceeds
therefrom) held by it as provided in Section 4.6 which, in the opinion of a
nationally recognized firm of independent public accountants expressed in a
written certification thereof delivered to the Trustee, are in excess of

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<PAGE>

the amount thereof which would then be required to be deposited to effect an
equivalent defeasance or covenant defeasance, as applicable, in accordance with
this Article.

     Section 4.8 Reinstatement.

     If the Trustee or any Paying Agent is unable to apply any money in
accordance with Section 4.7 by reason of any order or judgment of any court or
governmental authority enjoining, restraining or otherwise prohibiting such
application, then the Company's obligations under this Indenture and such
Securities shall be revived and reinstated as though no deposit had occurred
pursuant to Section 4.4 or 4.5, as the case may be, until such time as the
Trustee or Paying Agent is permitted to apply all such money in accordance with
Section 4.7; provided, however, that if the Company makes any payment of
principal of (or premium, if any) or interest, if any, on any such Security
following the reinstatement of its obligations, the Company shall be subrogated
to the rights of the Holders of such Securities to receive such payment from the
money held by the Trustee or Paying Agent.

                                   ARTICLE V

                                    REMEDIES

     Section 5.1 Events of Default.

     "Event of Default," wherever used herein with respect to the Securities of
any series, means any one of the following events (whatever the reason for such
Event of Default and whether it shall be voluntary or involuntary or be effected
by operation of law or pursuant to any judgment, decree or order of any court or
any order, rule or regulation of any administrative or governmental body):

     (1) the Company defaults in the payment of any interest upon any Security
of that series, including any Additional Interest in respect thereof, when it
becomes due and payable, and continuance of such default for a period of 30 days
(subject to the deferral of any due date in the case of an Extension Period); or

     (2) the Company defaults in the payment of the principal of (or premium, if
any, on) any Security of that series at its Maturity; or

     (3) the Company defaults in the performance, or breach, in any material
respect, of any of its covenants or warranties in this Indenture (other than a
covenant or warranty a default in the performance of which or the breach of
which is elsewhere in this Section specifically dealt with), and continuance of
such default or breach for a period of 90 days after there has been given, by
registered or certified mail, to the Company by the Trustee or to the Company
and the Trustee by the Holders of at least 25% in principal amount of the
Outstanding Securities of that series a written notice specifying such default
or breach and requiring it to be remedied; or

     (4) the entry of a an order for relief or decree by a court having
jurisdiction in the premises adjudging the Company a bankrupt or insolvent, or
approving as properly filed a

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<PAGE>

petition seeking reorganization, arrangement, adjustment or composition of or in
respect of the Company under any applicable United States federal or state
bankruptcy, insolvency, reorganization or other similar law, or appointing a
receiver, conservator, custodian, liquidator, assignee, trustee, sequestrator
(or other similar official) of the Company or of any substantial part of its
property or ordering the winding up or liquidation of its affairs, and the
continuance of any such decree or order unstayed and in effect for a period of
60 consecutive days; or

     (5) the institution by the Company of proceedings to be adjudicated a
bankrupt or insolvent, or the consent by it to the institution of bankruptcy or
insolvency proceedings against it, or the filing by it of a petition or answer
or consent seeking reorganization or relief under any applicable United States
federal or state bankruptcy, insolvency, reorganization or other similar law, or
the consent by it to the filing of any such petition or to the appointment of a
receiver, conservator, custodian, liquidator, assignee, trustee, sequestrator
(or other similar official) of the Company or of any substantial part of its
property, or the making by it of an assignment of the benefit of creditors, or
the admission by it in writing of its inability to pay its debts generally as
they become due and its willingness to be adjudicated a bankrupt, or the taking
of corporate action by the Company in furtherance of any such action; or

     (6) any other Event of Default provided with respect to Securities of that
series.

     Section 5.2 Acceleration of Maturity; Rescission and Annulment.

     If an Event of Default (other than an Event of Default specified in Section
5.1(4) or 5.1(5)) with respect to Securities of any series at the time
Outstanding occurs and is continuing, then and in every such case the Trustee or
the Holders of not less than 25% in principal amount of the Outstanding
Securities of that series may declare the principal amount (or, if the
Securities of that series are Discount Securities, such portion of the principal
amount as may be specified in the terms of that series) of all the Securities of
that series to be due and payable immediately, by a notice in writing to the
Company (and to the Trustee if given by Holders), provided that, in the case of
the Securities of a series issued to a ONEOK Capital Trust, if, upon an Event of
Default, the Trustee or the Holders of not less than 25% in principal amount of
the Outstanding Securities of that series fail to declare the principal of all
the Securities of that series to be immediately due and payable, the holders of
at least 25% in aggregate liquidation amount of the corresponding series of
Preferred Securities then outstanding shall have such right by a notice in
writing to the Company and the Trustee; and upon any such declaration such
principal amount (or specified portion thereof) of and the accrued interest
(including any Additional Interest) on all the Securities of such series shall
become immediately due and payable. Payment of principal and interest (including
any Additional Interest) on such Securities shall remain subordinated to the
extent provided in Article XIII notwithstanding that such amount shall become
immediately due and payable as herein provided. If an Event of Default specified
in Section 5.1(4) or 5.1(5) with respect to Securities of any series at the time
Outstanding occurs, the principal amount of all the Securities of that series
(or, if the Securities of that series are Discount Securities, such portion of
the principal amount of such Securities as may be specified by the terms of that
series) shall automatically, and without any declaration or other action on the
part of the Trustee or any Holder, become immediately due and payable.

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<PAGE>

     At any time after such a declaration of acceleration with respect to
Securities of any series has been made and before judgment or decree for payment
of the money due has been obtained by the Trustee as hereinafter in this Article
provided, the Holders of a majority in principal amount of the Outstanding
Securities of that series, by written notice to the Company and the Trustee, may
rescind and annul such declaration and its consequences if:

     (1) the Company has paid or deposited with the Trustee a sum sufficient to
pay:

     (A) all overdue installments of interest (including any Additional
Interest) on all Securities of that series,

     (B) the principal of (and premium, if any, on) any Securities of that
series which have become due otherwise than by such declaration of acceleration
and interest thereon at the rate borne by the Securities, and

     (C) all sums paid or advanced by the Trustee hereunder and the reasonable
compensation, expenses, disbursements and advances of the Trustee, its agents
and counsel; and

     (2) all Events of Default with respect to Securities of that series, other
than the non-payment of the principal of Securities of that series which has
become due solely by such acceleration, have been cured or waived as provided in
Section 5.13.

     In the case of Securities of a series issued to a ONEOK Capital Trust, the
holders of a majority in aggregate Liquidation Amount (as defined in the Trust
Agreement under which such ONEOK Capital Trust is formed) of the related series
of Preferred Securities issued by such ONEOK Capital Trust shall also have the
right to rescind and annul such declaration and its consequences by written
notice to the Company and the Trustee, subject to the satisfaction of the
conditions set forth in Clauses (1) and (2) above of this Section 5.2.

     No such rescission shall affect any subsequent default or impair any right
consequent thereon.

     Section 5.3 Collection of Indebtedness and Suits for Enforcement by
Trustee.

     The Company covenants that if:

     (1) default is made in the payment of any installment of interest
(including any Additional Interest) on any Security when such interest becomes
due and payable and such default continues for a period of 30 days, or

     (2) default is made in the payment of the principal of (and premium, if
any, on) any Security at the Maturity thereof the Company will, upon demand of
the Trustee, pay to the Trustee, for the benefit of the Holders of such
Securities, the whole amount then due and payable on such Securities for
principal, including any sinking fund payment or analogous obligations (and
premium, if any) and interest (including any Additional Interest); and, in
addition thereto, all amounts owing the Trustee under Section 6.7.

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<PAGE>

     If the Company fails to pay such amounts forthwith upon such demand, the
Trustee, in its own name and as trustee of an express trust, may institute a
judicial proceeding for the collection of the sums so due and unpaid, and may
prosecute such proceeding to judgment or final decree, and may enforce the same
against the Company or any other obligor upon the Securities and collect the
moneys adjudged or decreed to be payable in the manner provided by law out of
the property of the Company or any other obligor upon the Securities, wherever
situated.

     If an Event of Default with respect to Securities of any series occurs and
is continuing, the Trustee may in its discretion proceed to protect and enforce
its rights and the rights of the Holders of Securities of such series by such
appropriate judicial proceedings as the Trustee shall deem most effectual to
protect and enforce any such rights, whether for the specific enforcement of any
covenant or agreement in this Indenture or in aid of the exercise of any power
granted herein, or to enforce any other proper remedy.

     Section 5.4 Trustee May File Proofs of Claim.

     In case of the pendency of any receivership, conservatorship, insolvency,
liquidation, bankruptcy, reorganization, arrangement, adjustment, composition or
other judicial or administrative proceeding relative to the Company or any other
obligor upon the Securities or the property of the Company of such other obligor
or their creditors, the Trustee (irrespective of whether the principal of the
Securities of any series shall then be due and payable as therein expressed or
by declaration or otherwise and irrespective of whether the Trustee shall have
made any demand on the Company for the payment of overdue principal (and
premium, if any) or interest (including any Additional Interest)) shall be
entitled and empowered, by intervention in such proceeding or otherwise,

     (i)   to file and prove a claim for the whole amount of principal (and
premium, if any) and interest (including any Additional Interest) owing and
unpaid in respect of the Securities and to file such other papers or documents
as may be necessary or advisable and to take any and all actions as are
authorized under the Trust Indenture Act in order to have the claims of the
Holders, the Trustee and any predecessor to the Trustee under Section 6.7
allowed in any such judicial or administrative proceedings; and

     (ii)  in particular, the Trustee shall be authorized to collect and receive
any moneys or other property payable or deliverable on any such claims and to
distribute the same in accordance with Section 5.6; and

     (iii) any custodian, conservator, receiver, assignee, trustee, liquidator,
sequestrator (or other similar official) in any such judicial or administrative
proceeding is hereby authorized by each Holder to make such payments to the
Trustee for distribution in accordance with Section 5.6, and in the event that
the Trustee shall consent to the making of such payments directly to the
Holders, to pay to the Trustee any amount due to it and any predecessor Trustee
under Section 6.7.

     Nothing herein contained shall be deemed to authorize the Trustee to
authorize or consent to or accept or adopt on behalf of any Holder any plan of
reorganization, arrangement, adjustment or composition affecting the Securities
or the rights of any Holder thereof, or to

                                       42

<PAGE>

authorize the Trustee to vote in respect of the claim of any Holder in any such
proceeding; provided, however, that the Trustee may, on behalf of the Holders,
vote for the election of a trustee in bankruptcy or similar official and be a
member of a creditors' or other similar committee.

     Section 5.5 Trustee May Enforce Claim Without Possession of Securities.

     All rights of action and claims under this Indenture or the Securities may
be prosecuted and enforced by the Trustee without the possession of any of the
Securities or the production thereof in any proceeding relating thereto, and any
such proceeding instituted by the Trustee shall be brought in its own name as
trustee of an express trust, and any recovery of judgment shall, after provision
for the payment of all the amounts owing the Trustee and any predecessor Trustee
under Section 6.7, its agents and counsel, be for the ratable benefit of the
Holders of the Securities in respect of which such judgment has been recovered.

     Section 5.6 Application of Money Collected.

     Any money or property collected or to be applied by the Trustee with
respect to a series of Securities pursuant to this Article shall be applied in
the following order, at the date or dates fixed by the Trustee and, in case of
the distribution of such money or property on account of principal (or premium,
if any) or interest (including any Additional Interest), upon presentation of
the Securities and the notation thereon of the payment if only partially paid
and upon surrender thereof if fully paid:

     FIRST: To the payment of all amounts due the Trustee and any predecessor
Trustee under Section 6.7;

     SECOND: Subject to Article XIII, to the payment of the amounts then due and
unpaid upon such series of Securities for principal (and premium, if any) and
interest (including any Additional Interest), in respect of which or for the
benefit of which such money has been collected, ratably, without preference or
priority of any kind, according to the amounts due and payable on such series of
Securities for principal (and premium, if any) and interest (including any
Additional Interest), respectively; and

     THIRD: The balance, if any, to the Person or Persons entitled thereto.

     Section 5.7 Limitation on Suits.

     Subject to Section 5.8, no Holder of any Securities of any series shall
have any right to institute any proceeding, judicial or otherwise, with respect
to this Indenture or for the appointment of a receiver, conservator, assignee,
trustee, liquidator, sequestrator (or other similar official) or for any other
remedy hereunder, unless:

     (1) an Event of Default with respect to Securities of any series has
occurred and is continuing, and the Company has not paid or deposited with the
Trustee all amounts then payable;

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<PAGE>

     (2) such Holder has previously given written notice to the Trustee of a
continuing Event of Default with respect to the Securities of that series;

     (3) the Holders of not less than 25% in principal amount of the Outstanding
Securities of that series shall have made written request to the Trustee to
institute proceedings in respect of such Event of Default in its own name as
Trustee hereunder;

     (4) such Holder or Holders have offered to the Trustee reasonable indemnity
against the costs, expenses and liabilities to be incurred in compliance with
such request;

     (5) the Trustee for 60 days after its receipt of such notice, request and
offer of indemnity has failed to institute any such proceeding; and

     (6) no direction inconsistent with such written request has been given to
the Trustee during such 60-day period by the Holders of a majority in principal
amount of the Outstanding Securities of that series; it being understood and
intended that no one or more of such Holders shall have any right in any manner
whatever by virtue of, or by availing itself of, any provision of this Indenture
to affect, disturb or prejudice the rights of any other Holders of Securities,
or to obtain or to seek to obtain priority or preference over any other of such
Holders or to enforce any right under this Indenture, except in the manner
herein provided and for the equal and ratable benefit of all such Holders.

     Section 5.8 Unconditional Right of Holders to Receive Principal, Premium
and Interest; Direct Action by Holders of Preferred Securities.

     Notwithstanding any other provision in this Indenture, the Holder of any
Security shall have the right which is absolute and unconditional to receive
payment of the principal of (and premium, if any) and (subject to Section 3.7)
interest (including any Additional Interest) on such Security on the respective
Stated Maturities expressed in such Security (or, in the case of redemption, on
the Redemption Date) and to institute suit for the enforcement of any such
payment, and such right shall not be impaired without the consent of such
Holder. In the case of Securities of a series issued to a ONEOK Capital Trust,
any holder of the corresponding series of Preferred Securities issued by such
ONEOK Capital Trust shall have the right, upon the occurrence of an Event of
Default described in Section 5.1(1) or 5.1(2), to institute a suit directly
against the Company for enforcement of payment to such holder of principal of
(premium, if any) and (subject to Section 3.7) interest (including any
Additional Interest) on the Securities having a principal amount equal to the
aggregate Liquidation Amount (as defined in the Trust Agreement under which such
ONEOK Capital Trust is formed) of such Preferred Securities of the corresponding
series held by such holder.

     Section 5.9 Restoration of Rights and Remedies.

     If the Trustee, any Holder or any holder of Preferred Securities has
instituted any proceeding to enforce any right or remedy under this Indenture
and such proceeding has been discontinued or abandoned for any reason, or has
been determined adversely to the Trustee, such Holder or such holder of
Preferred Securities, then and in every such case the Company, the Trustee, the
Holders and such holder of Preferred Securities shall, subject to any
determination in such proceeding, be restored severally and respectively to
their former positions hereunder, and

                                       44

<PAGE>

thereafter all rights and remedies of the Trustee, the Holders and the holders
of Preferred Securities shall continue as though no such proceeding had been
instituted.

     Section 5.10 Rights and Remedies Cumulative.

     Except as otherwise provided in the last paragraph of Section 3.6, no right
or remedy herein conferred upon or reserved to the Trustee or to the Holders is
intended to be exclusive of any other right or remedy, and every right and
remedy shall, to the extent permitted by law, be cumulative and in addition to
every other right and remedy given hereunder or now or hereafter existing at law
or in equity or otherwise. The assertion or employment of any right or remedy
hereunder, or otherwise, shall not prevent the concurrent assertion or
employment of any other appropriate right or remedy.

     Section 5.11 Delay or Omission Not Waiver.

     No delay or omission of the Trustee, any Holder of any Security or any
holder of any Preferred Security to exercise any right or remedy accruing upon
any Event of Default shall impair any such right or remedy or constitute a
waiver of any such Event of Default or an acquiescence therein.

     Every right and remedy given by this Article or by law to the Trustee or to
the Holders and the right and remedy given to the holders of Preferred
Securities by Section 5.8 may be exercised from time to time, and as often as
may be deemed expedient, by the Trustee, the Holders or the holders of Preferred
Securities, as the case may be.

     Section 5.12 Control by Holders.

     The Holders of not less than a majority in principal amount of the
Outstanding Securities of any series shall have the right to direct the time,
method and place of conducting any proceeding for any remedy available to the
Trustee or exercising any trust or power conferred on the Trustee, with respect
to the Securities of such series, provided that:

     (1) such direction shall not be in conflict with any rule of law or with
this Indenture,

     (2) the Trustee may take any other action deemed proper by the Trustee
which is not inconsistent with such direction, and

     (3) subject to the provisions of Section 6.1, the Trustee shall have the
right to decline to follow such direction if a Responsible Officer or Officers
of the Trustee shall, in good faith, determine that the proceeding so directed
would be unjustly prejudicial to the Holders not joining in any such direction
or would involve the Trustee in personal liability.

     Section 5.13 Waiver of Past Defaults.

     The Holders of not less than a majority in principal amount of the
Outstanding Securities of any series and, in the case of any Securities of a
series issued to a ONEOK Capital Trust, the holders of a majority in aggregate
liquidation amount of the Preferred Securities issued by such

                                       45

<PAGE>

ONEOK Capital Trust may waive any past default hereunder and its consequences
with respect to such series except a default:

     (1) in the payment of the principal of (or premium, if any) or interest
(including any Additional Interest) on any Security of such series, unless such
default has been cured and the Company has paid to or deposited with the Trustee
a sum sufficient to pay all matured installments of interest (including
Additional Interest) and all principal (and premium, if any) on all Securities
due otherwise than by acceleration, or

     (2) in respect of a covenant or provision hereof which under Article IX
cannot be modified or amended without the consent of the Holder of each
Outstanding Security of such series affected.

     Any such waiver shall be deemed to be on behalf of the Holders of all the
Securities of such series or, in the case of a waiver by holders of Preferred
Securities issued by such ONEOK Capital Trust, by all holders of Preferred
Securities issued by such ONEOK Capital Trust.

     Upon any such waiver, such default shall cease to exist, and any Event of
Default arising therefrom shall be deemed to have been cured, for every purpose
of this Indenture; but no such waiver shall extend to any subsequent or other
default or impair any right consequent thereon.

     Section 5.14 Undertaking for Costs.

     All parties to this Indenture agree, and each Holder of any Security by his
acceptance thereof shall be deemed to have agreed, that any court may in its
discretion require, in any suit for the enforcement of any right or remedy under
this Indenture, or in any suit against the Trustee for any action taken or
omitted by it as Trustee, the filing by any party litigant in such suit of an
undertaking to pay the costs of such suit, and that such court may in its
discretion assess reasonable costs, including reasonable attorneys' fees,
against any party litigant in such suit, having due regard to the merits and
good faith of the claims or defenses made by such party litigant; but the
provisions of this Section shall not apply to any suit instituted by the
Trustee, to any suit instituted by any Holder, or group of Holders, holding in
the aggregate more than 10% in principal amount of the Outstanding Securities of
any series, or to any suit instituted by any Holder for the enforcement of the
payment of the principal of (or premium, if any) or interest (including any
Additional Interest) on any Security on or after the respective Stated
Maturities expressed in such Security.

     Section 5.15 Waiver of Usury, Stay or Extension Laws.

     The Company covenants (to the extent that it may lawfully do so) that it
will not at any time insist upon, or plead, or in any manner whatsoever claim or
take the benefit or advantage of, any usury, stay or extension law wherever
enacted, now or at any time hereafter in force, which may affect the covenants
or the performance of this Indenture; and the Company (to the extent that it may
lawfully do so) hereby expressly waives any benefit or advantage of any such
law, and covenants that it will not hinder, delay or impede the execution of any
power herein granted to the Trustee, but will suffer and permit the execution of
every such power as though no such law had been enacted.

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<PAGE>

                                   ARTICLE VI

                                   THE TRUSTEE

     Section 6.1 Certain Duties and Responsibilities.

     (a) Except during the continuance of an Event of Default,

         (1) the Trustee undertakes to perform such duties and only such duties
as are specifically set forth in this Indenture, and no implied covenants or
obligations shall be read into this Indenture against the Trustee; and

         (2) in the absence of bad faith on its part, the Trustee may
conclusively rely, as to the truth of the statements and the correctness of the
opinions expressed therein, upon certificates or opinions furnished to the
Trustee and conforming to the requirements of this Indenture; but in the case of
any such certificates or opinions which by any provisions hereof are
specifically required to be furnished to the Trustee, the Trustee shall be under
a duty to examine the same to determine whether or not they conform to the
requirements of this Indenture.

     (b) In case an Event of Default has occurred and is continuing, the Trustee
shall exercise such of the rights and powers vested in it by this Indenture, and
use the same degree of care and skill in their exercise, as a prudent person
would exercise or use under the circumstances in the conduct of his own affairs.

     (c) No provision of this Indenture shall be construed to relieve the
Trustee from liability for its own negligent action, its own negligent failure
to act, or its own willful misconduct except that:

         (1) this Subsection shall not be construed to limit the effect of
Subsection (a) of this Section;

         (2) the Trustee shall not be liable for any error of judgment made in
good faith by a Responsible Officer; unless it shall be proved that the Trustee
was negligent in ascertaining the pertinent facts; and

         (3) the Trustee shall not be liable with respect to any action taken or
omitted to be taken by it in good faith in accordance with the direction of
Holders pursuant to Section 5.12 relating to the time, method and place of
conducting any proceeding for any remedy available to the Trustee, or exercising
any trust or power conferred upon the Trustee, under this Indenture with respect
to the Securities of such series.

     (d) No provision of this Indenture shall require the Trustee to expend or
risk its own funds or otherwise incur any financial liability in the performance
of any of its duties hereunder, or in the exercise of any of its rights or
powers, if there shall be reasonable grounds for believing that repayment of
such funds or adequate indemnity against such risk or liability is not
reasonably assured to it.

                                       47

<PAGE>

     (e) Whether or not therein expressly so provided, every provision of this
Indenture relating to the conduct or affecting the liability of or affording
protection to the Trustee shall be subject to the provisions of this Section.

     Section 6.2 Notice of Defaults.

     Within 90 days after actual knowledge by a Responsible Officer of the
Trustee of the occurrence of any default hereunder with respect to the
Securities of any series, the Trustee shall transmit by mail to all Holders of
Securities of such series, as their names and addresses appear in the Securities
Register, notice of such default, unless such default shall have been cured or
waived; provided, however, that, except in the case of a default in the payment
of the principal of (or premium, if any) or interest (including any Additional
Interest) on any Security of such series, the Trustee shall be protected in
withholding such notice if and so long as the board of directors, the executive
committee or a trust committee of directors and/or Responsible Officers of the
Trustee in good faith determines that the withholding of such notice is in the
interests of the Holders of Securities of such series; and provided, further,
that, in the case of any default of the character specified in Section 5.1(3),
no such notice to Holders of Securities of such series shall be given until at
least 30 days after the occurrence thereof. For the purpose of this Section, the
term "default" means any event which is, or after notice or lapse of time or
both would become, an Event of Default with respect to Securities of such
series.

     Section 6.3 Certain Rights of Trustee.

     Subject to the provisions of Section 6.1:

     (a) the Trustee may rely and shall be protected in acting or refraining
from acting upon any resolution, certificate, statement, instrument, opinion,
report, notice, request, direction, consent, order, bond, debenture, Security or
other paper or document believed by it to be genuine and to have been signed or
presented by the proper party or parties;

     (b) any request or direction of the Company mentioned herein shall be
sufficiently evidenced by a Company Request or Company Order and any resolution
of the Board of Directors may be sufficiently evidenced by a Board Resolution;

     (c) whenever in the administration of this Indenture the Trustee shall deem
it desirable that a matter be proved or established prior to taking, suffering
or omitting any action hereunder, the Trustee (unless other evidence be herein
specifically prescribed) may, in the absence of bad faith on its part, rely upon
an Officers' Certificate;

     (d) the Trustee may consult with counsel and the advice of such counsel or
any Opinion of Counsel shall be full and complete authorization and protection
in respect of any action taken, suffered or omitted by it hereunder in good
faith and in reliance thereon;

     (e) the Trustee shall be under no obligation to exercise any of the rights
or powers vested in it by this Indenture at the request or direction of any of
the Holders pursuant to this Indenture, unless such Holders shall have offered
to the Trustee reasonable security or indemnity against the costs, expenses and
liabilities which might be incurred by it in compliance with such request or
direction;

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     (f) the Trustee shall not be bound to make any investigation into the facts
or matters stated in any resolution, certificate, statement, instrument,
opinion, report, notice, request, direction, consent, order, bond, indenture,
Security or other paper or document, but the Trustee in its discretion may make
such inquiry or investigation into such facts or matters as it may see fit, and,
if the Trustee shall determine to make such inquiry or investigation, it shall
be entitled to examine the books, records and premises of the Company,
personally or by agent or attorney;

     (g) the Trustee may execute any of the trusts or powers hereunder or
perform any duties hereunder either directly or by or through agents or
attorneys and the Trustee shall not be responsible for any misconduct or
negligence on the part of any agent or attorney appointed with due care by it
hereunder;

     (h) The Trustee shall not be required to take notice or be deemed to have
notice of any default hereunder except during any period while it is serving as
Paying Agent with respect to a Security, a default in any of the payments to the
Trustee required to be made with respect to such Security, unless a Responsible
Officer of the Trustee shall be specifically notified in writing of such default
by the Company or the holders of at least 25% in principal amount of the
Outstanding Securities affected by such default, and in the absence of such
notice so delivered, the Trustee may conclusively assume there is no default
except as aforesaid; and

     (i) Notwithstanding anything herein or in any of the Securities to the
contrary, any notice to the Trustee which is permitted or required to be given
pursuant to this Indenture or the Securities shall not be effective unless and
until given in writing to a Responsible Officer located at the Corporate Trust
Office.

     Section 6.4 Not Responsible for Recitals or Issuance of Securities.

     The recitals contained herein and in the Securities, except the Trustee's
certificates of authentication, shall be taken as the statements of the Company,
and neither the Trustee nor any Authenticating Agent assumes any responsibility
for their correctness. The Trustee makes no representations as to the validity
or sufficiency of this Indenture or of the Securities. Neither the Trustee nor
any Authenticating Agent shall be accountable for the use or application by the
Company of the Securities or the proceeds thereof.

     Section 6.5 May Hold Securities.

     The Trustee, any Authenticating Agent, any Paying Agent, any Securities
Registrar or any other agent of the Company, in its individual or any other
capacity, may become the owner or pledgee of Securities and, subject to Sections
6.8 and 6.13, may otherwise deal with the Company with the same rights it would
have if it were not Trustee, Authenticating Agent, Paying Agent, Securities
Registrar or such other agent.

     Section 6.6 Money Held in Trust.

     Money held by the Trustee in trust hereunder need not be segregated from
other funds except to the extent required by law. The Trustee shall be under no
liability for interest on any money received by it hereunder except as otherwise
agreed with the Company.

     Section 6.7 Compensation and Reimbursement.

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<PAGE>

     The Company agrees:

     (1) to pay to the Trustee from time to time reasonable compensation for all
services rendered by it hereunder in such amounts as the Company, and the
Trustee shall agree from time to time (which compensation shall not be limited
by any provision of law in regard to the compensation of a trustee of an express
trust);

     (2) to reimburse the Trustee upon its request for all reasonable expenses,
disbursements and advances incurred or made by the Trustee in accordance with
any provision of this Indenture (including the reasonable compensation and the
expenses and disbursements of its agents and counsel), except any such expense,
disbursement or advance as may be attributable to its negligence or bad faith;

     (3) to indemnify the Trustee for, and to hold it harmless against, any
loss, liability or expense (including the reasonable compensation and the
expenses and disbursements of its agents and counsel) incurred without
negligence or bad faith, arising out of or in connection with the acceptance or
administration of this trust or the performance of its duties hereunder,
including the costs and expenses of defending itself against any claim or
liability in connection with the exercise or performance of any of its powers or
duties hereunder. This indemnification shall survive the termination of this
Indenture and the resignation or removal of the Trustee; and

     (4) Since each ONEOK Trust is being formed solely to facilitate an
investment in the Trust Securities, the Company, as Depositor of each ONEOK
Capital Trust under the Trust Agreement, hereby covenants to pay all debts and
obligations (other than with respect to the Preferred Securities and the Common
Securities) and all reasonable costs and expenses of such ONEOK Capital Trust
(including without limitation all reasonable costs and expenses relating to the
organization of the ONEOK Capital Trust, the fees and expenses of the trustees
and all costs and expenses relating to the operation of the ONEOK Capital Trust)
and to pay any and all taxes, duties, assessments or governmental charges of
whatever nature (other than withholding taxes) imposed on each ONEOK Capital
Trust by the United States, or any taxing authority, so that the net amounts
received and retained by each ONEOK Capital Trust and the Property Trustee after
paying such expenses will be equal to the amounts each ONEOK Capital Trust and
the Property Trustee would have received had no such costs or expenses been
incurred by or imposed on each ONEOK Trust.

     To secure the Company's payment obligations in this Section, the Company,
and the Holders agree that the Trustee shall have a lien prior to the Securities
on all money or property held or collected by the Trustee. Such lien shall
survive the satisfaction and discharge of this Indenture.

     When the Trustee incurs expenses or renders services after an Event of
Default specified in Section 5.1(4) or (5) occurs, the expenses and the
compensation for the services are intended

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<PAGE>

to constitute expenses of administration under the Bankruptcy Reform Act of 1978
or any successor statute.

     Section 6.8 Disqualification; Conflicting Interests.

     The Trustee for the Securities of any series issued hereunder shall be
subject to the provisions of Section 310(b) of the Trust Indenture Act. Nothing
herein shall prevent the Trustee from filing with the Commission the application
referred to in the second to last paragraph of said Section 310(b). Each Trust
Agreement and ONEOK Capital Guarantee are hereby excluded from the provision of
Section 310(b)(1) of the Trust Indenture Act.

     Section 6.9 Corporate Trustee Required; Eligibility.

     There shall at all times be a Trustee hereunder which shall be

     (a) an entity organized and doing business under the laws of the United
States of America or of any State or Territory or the District of Columbia,
authorized under such laws to exercise corporate trust powers and subject to
supervision or examination by United States federal, state, territorial or
District of Columbia authority, or

     (b) an entity or other Person organized and doing business under the laws
of a foreign government that is permitted to act as Trustee pursuant to a rule,
regulation or order of the Commission, authorized under such laws to exercise
corporate trust powers, and subject to supervision or examination by authority
of such foreign government or a political subdivision thereof substantially
equivalent to supervision or examination applicable to United States
institutional trustees, in either case having a combined capital and surplus of
at least $50,000,000, subject to supervision or examination by United States
federal or state authority. If such entity publishes reports of condition at
least annually, pursuant to law or to the requirements of the aforesaid
supervising or examining authority, then, for the purposes of this Section, the
combined capital and surplus of such entity shall be deemed to be its combined
capital and surplus as set forth in its most recent report of condition so
published. If at any time the Trustee shall cease to be eligible in accordance
with the provisions of this Section, it shall resign immediately in the manner
and with the effect hereinafter specified in this Article. Neither the Company,
nor any Person directly or indirectly controlling, controlled by or under common
control with the Company shall serve as Trustee for the Securities of any series
issued hereunder.

     Section 6.10 Resignation and Removal; Appointment of Successor.

     (a) No resignation or removal of the Trustee and no appointment of a
successor Trustee pursuant to this Article shall become effective until the
acceptance of appointment by the successor Trustee under Section 6.11.

     (b) The Trustee may resign at any time with respect to the Securities of
one or more series by giving written notice thereof to the Company. If an
instrument of acceptance by a successor Trustee shall not have been delivered to
the Trustee within 30 days after the giving of such notice of resignation, the
resigning Trustee may petition any court of competent jurisdiction for the
appointment of a successor Trustee with respect to the Securities of such
series.

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     (c) The Trustee may be removed at any time with respect to the Securities
of any series by Act of the Holders of a majority in principal amount of the
Outstanding Securities of such series, delivered to the Trustee and to the
Company.

     (d) If at any time:

         (1) the Trustee shall fail to comply with Section 6.8 after written
request therefor by the Company, or by any Holder who has been a bona fide
Holder of a Security for at least six months, or

         (2) the Trustee shall cease to be eligible under Section 6.9 and shall
fail to resign after written request therefor by the Company, or by any such
Holder, or

         (3) the Trustee shall become incapable of acting or shall be adjudged a
bankrupt or insolvent or a receiver, conservator, liquidator, or similar
official of the Trustee or of its property shall be appointed or any public
officer shall take charge or control of the Trustee or of its property or
affairs for the purpose of rehabilitation, receivership,conservation or
liquidation, then, in any such case, (i) the Company acting pursuant to the
authority of a Board Resolution, may remove the Trustee with respect to all
Securities, or (ii) subject to Section 5.14, any Holder who has been a bona fide
Holder of a Security for at least six months may, on behalf of himself and all
others similarly situated, petition any court of competent jurisdiction for the
removal of the Trustee with respect to all Securities and the appointment of a
successor Trustee or Trustees.

     (e) If the Trustee shall resign, be removed or become incapable of acting,
or if a vacancy shall occur in the office of Trustee for any cause with respect
to the Securities of one or more series, the Company, by a Board Resolution,
shall promptly appoint a successor Trustee with respect to the Securities of
that or those series. If, within one year after such resignation, removal or
incapability, or the occurrence of such vacancy, a successor Trustee with
respect to the Securities of any series shall be appointed by Act of the Holders
of a majority in principal amount of the Outstanding Securities of such series
delivered to the Company and the retiring Trustee, the successor Trustee so
appointed shall, forthwith upon its acceptance of such appointment, become the
successor Trustee with respect to the Securities of such series and supersede
the successor Trustee appointed by the Company. If no successor Trustee with
respect to the Securities of any series shall have been so appointed by the
Company or the Holders and accepted appointment in the manner hereinafter
provided, any Holder who has been a bona fide Holder of a Security for at least
six months may, subject to Section 5.14, on behalf of himself and all others
similarly situated, petition any court of competent jurisdiction for the
appointment of a successor Trustee with respect to the Securities of such
series.

     (f) The Company shall give notice of each resignation and each removal of
the Trustee with respect to the Securities of any series and each appointment of
a successor Trustee with respect to the Securities of any series by mailing
written notice of such event by first-class mail, postage prepaid, to the
Holders of Securities of such series as their names and addresses appear in the
Securities Register. Each notice shall include the name of the successor Trustee
with respect to the Securities of such series and the address of its Corporate
Trust Office.

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<PAGE>

     Section 6.11 Acceptance of Appointment by Successor.

     (a) In case of the appointment hereunder of a successor Trustee with
respect to all Securities, every such successor Trustee so appointed shall
execute, acknowledge and deliver to the Company and to the retiring Trustee an
instrument accepting such appointment, and thereupon the resignation or removal
of the retiring Trustee shall become effective and such successor Trustee,
without any further act, deed or conveyance, shall become vested with all the
rights, powers, trusts and duties of the retiring Trustee; but, on the request
of the Company or the successor Trustee, such retiring Trustee shall, upon
payment of its charges, execute and deliver an instrument transferring to such
successor Trustee all the rights, powers and trusts of the retiring Trustee and
shall duly assign, transfer and deliver to such successor Trustee all property
and money held by such retiring Trustee hereunder.

     (b) In case of the appointment hereunder of a successor Trustee with
respect to the Securities of one or more (but not all) series, the Company, the
retiring Trustee and each successor Trustee with respect to the Securities of
any series shall execute and deliver an indenture supplemental hereto wherein
each successor Trustee shall accept such appointment and which (1) shall contain
such provisions as shall be necessary or desirable to transfer and confirm to,
and to vest in, each successor Trustee all the rights, powers, trusts and duties
of the retiring Trustee with respect to the Securities of that or those series
to which the appointment of such successor Trustee relates, (2) if the retiring
Trustee is not retiring with respect to all Securities, shall contain such
provisions as shall be deemed necessary or desirable to confirm that all the
rights, powers, trusts and duties of the retiring Trustee with respect to the
Securities of that or those series as to which the retiring Trustee is not
retiring shall continue to be vested in the retiring Trustee, and (3) shall add
to or change any of the provisions of this Indenture as shall be necessary to
provide for or facilitate the administration of the trusts hereunder by more
than one Trustee, it being understood that nothing herein or in such
supplemental indenture shall constitute such Trustees co-trustees of the same
trust and that each such Trustee shall be trustee of a trust or trusts hereunder
separate and apart from any trust or trusts hereunder administered by any other
such Trustee; and upon the execution and delivery of such supplemental indenture
the resignation or removal of the retiring Trustee shall become effective to the
extent provided therein and each such successor Trustee, without any further
act, deed or conveyance, shall become vested with all the rights, powers,
trusts, and duties of the retiring Trustee with respect to the Securities of any
series to which the appointment of such successor Trustee relates; but, on
request of the Company or any successor Trustee, such retiring Trustee shall
duly assign, transfer and deliver to such successor Trustee all property and
money held by such retiring Trustee hereunder with respect to the Securities of
that or those series to which the appointment of such successor Trustee relates.

     (c) Upon request of any such successor Trustee, the Company shall execute
any and all instruments for more fully and certainly vesting in and confirming
to such successor Trustee all rights, powers and trusts referred to in paragraph
(a) or (b) of this Section, as the case may be.

     (d) No successor Trustee shall accept its appointment unless at the time of
such acceptance such successor Trustee shall be qualified and eligible under
this Article.

     Section 6.12 Merger, Conversion, Consolidation or Succession to Business.

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<PAGE>

     Any entity into which the Trustee may be merged or converted or with which
it may be consolidated, or any entity resulting from any merger, conversion or
consolidation to which the Trustee shall be a party, or any entity succeeding to
all or substantially all of the corporate trust business of the Trustee, shall
be the successor of the Trustee hereunder, provided such entity shall be
otherwise qualified and eligible under this Article, without the execution or
filing of any paper or any further act on the part of any of the parties hereto.
In case any Securities shall have been authenticated, but not delivered, by the
Trustee then in office, any successor by merger, conversion or consolidation to
such authenticating Trustee may adopt such authentication and deliver the
Securities so authenticated, and in case any Securities shall not have been
authenticated, any successor to the Trustee may authenticate such Securities
either in the name of any predecessor Trustee or in the name of such successor
Trustee, and in all cases the certificate of authentication shall have the full
force which it is provided anywhere in the Securities or in this Indenture that
the certificate of the Trustee shall have.

     Section 6.13 Preferential Collection of Claims Against Company.

     If and when the Trustee shall be or become a creditor of the Company or any
other obligor upon the Securities, the Trustee shall be subject to the
provisions of the Trust Indenture Act regarding the collection of claims against
the Company or any such other obligor.

     Section 6.14 Appointment of Authenticating Agent.

     The Trustee may appoint an Authenticating Agent or Agents with respect to
one or more series of Securities which shall be authorized to act on behalf of
the Trustee to authenticate Securities of such series issued upon original issue
and upon exchange, registration of transfer or partial redemption thereof or
pursuant to Section 3.6, and Securities so authenticated shall be entitled to
the benefits of this Indenture and shall be valid and obligatory for all
purposes as if authenticated by the Trustee hereunder. Wherever reference is
made in this Indenture to the authentication and delivery of Securities by the
Trustee or the Trustee's certificate of authentication, such reference shall be
deemed to include authentication and delivery on behalf of the Trustee by an
Authenticating Agent. Each Authenticating Agent shall be acceptable to the
Company shall at all times be an entity organized and doing business under the
laws of the United States of America, or of any State or Territory or the
District of Columbia, authorized under such laws to act as Authenticating Agent,
having a combined capital and surplus of not less than $50,000,000, except for
Affiliates of the Trustee, and subject to supervision or examination by United
States federal or state authority. If such Authenticating Agent publishes
reports of condition at least annually, pursuant to law or to the requirements
of said supervising or examining authority, then for the purposes of this
Section the combined capital and surplus of such Authenticating Agent shall be
deemed to be its combined capital and surplus as set forth in its most recent
report of condition so published. If at any time an Authenticating Agent shall
cease to be eligible in accordance with the provisions of this Section, such
Authenticating Agent shall resign immediately in the manner and with the effect
specified in this Section.

     Any entity into which an Authenticating Agent may be merged or converted or
with which it may be consolidated, or any entity resulting from any merger,
conversion or consolidation to which such Authenticating Agent shall be a party,
or any entity succeeding to all or substantially all of the corporate trust
business of an Authenticating Agent shall be the

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<PAGE>

successor Authenticating Agent hereunder, provided such entity shall be
otherwise eligible under this Section, without the execution or filing of any
paper or any further act on the part of the Trustee or the Authenticating Agent.

     An Authenticating Agent may resign at any time by giving written notice
thereof to the Trustee and the Company. The Trustee may at any time terminate
the agency of an Authenticating Agent by giving written notice thereof to such
Authenticating Agent and the Company. Upon receiving such a notice of
resignation or upon such a termination, or in case at any time such
Authenticating Agent shall cease to be eligible in accordance with the
provisions of this Section, the Trustee may appoint a successor Authenticating
Agent which shall be acceptable to the Company and shall give notice of such
appointment in the manner provided in Section 1.6 to all Holders of Securities
of the series with respect to which such Authenticating Agent will serve. Any
successor Authenticating Agent upon acceptance of its appointment hereunder
shall become vested with all the rights, powers and duties of its predecessor
hereunder, with like effect as if originally named as an Authenticating Agent.
No successor Authenticating Agent shall be appointed unless eligible under the
provision of this Section.

     The Trustee agrees to pay to each Authenticating Agent from time to time
reasonable compensation for its services under this Section, and the Trustee
shall be entitled to be reimbursed for such payments, subject to the provisions
of Section 6.7.

     If an appointment with respect to one or more series is made pursuant to
this Section, the Securities of such series may have endorsed thereon, in
addition to the Trustee's certificate of authentication, an alternative
certificate of authentication in the following form:

     This is one of the Securities referred to in the within-mentioned
Indenture.

Dated:_____________________________


As Trustee

By:________________________________
      As Authenticating Agent

By:________________________________
         Authorized Officer

                                   ARTICLE VII

                HOLDER'S LISTS AND REPORTS BY TRUSTEE AND COMPANY

     Section 7.1 Company to Furnish Trustee Names and Addresses of Holders.

     The Company will furnish or cause to be furnished to the Trustee:

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<PAGE>

     (a) [quarterly, semi-annually], not more than 15 days after each regular
record date for each Interest Payment Date in each year, a list, in such form as
the Trustee may reasonably require, of the names and addresses of the Holders as
of each such record-date, and

     (b) at such other times as the Trustee may request in writing, within 30
days after the receipt by the Company of any such request, a list of similar
form and content as of a date not more than 15 days prior to the time such list
is furnished, excluding from any such list names and addresses received by the
Trustee in its capacity as Securities Registrar.

     Section 7.2 Preservation of Information, Communications to Holders.

     (a) The Trustee shall preserve, in as current a form as is reasonably
practicable, the names and addresses of Holders contained in the most recent
list furnished to the Trustee as provided in Section 7.1 and the names and
addresses of Holders received by the Trustee in its capacity as Securities
Registrar. The Trustee may destroy any list furnished to it as provided in
Section 7.1 upon receipt of a new list so furnished.

     (b) The rights of Holders to communicate with other Holders with respect to
their rights under this Indenture or under the Securities, and the corresponding
rights and privileges of the Trustee, shall be as provided in the Trust
Indenture Act.

     (c) Every Holder of Securities, by receiving and holding the same, agrees
with the Company and the Trustee that none of the Company the Trustee or any
agent of either of them shall be held accountable by reason of the disclosure of
information as to the names and addresses of the Holders made pursuant to the
Trust Indenture Act.

     Section 7.3 Reports by Trustee.

     (a) The Trustee shall transmit to Holders such reports concerning the
Trustee and its actions under this Indenture as may be required pursuant to the
Trust Indenture Act, at the times and in the manner provided pursuant thereto.

     (b) Reports so required to be transmitted at stated intervals of not more
than 12 months shall be transmitted no later than 60 days following May 15 in
each calendar year, commencing after the first issuance of Securities under this
Indenture.

     (c) A copy of each such report shall, at the time of such transmission to
Holders, be filed by the Trustee with each stock exchange upon which any
Securities are listed and also with the Commission. The Company will notify the
Trustee when any Securities are listed on any stock exchange.

     Section 7.4 Reports by the Company.

     The Company shall file with the Trustee and with the Commission, and
transmit to Holders, such information, documents and other reports, and such
summaries thereof, as may be required pursuant to the Trust Indenture Act at the
times and in the manner provided in the Trust Indenture Act; provided that any
such information, documents or reports required to be filed with the Commission
pursuant to Section 13 or Section 15(d) of the Exchange Act shall be filed with

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<PAGE>

the Trustee within 15 days after the same is required to be filed with the
Commission. Notwithstanding that the Company may not be required to remain
subject to the reporting requirements of Section 13 or 15(d) of the Exchange
Act, the Company shall continue to file with the Commission and provide the
Trustee with the annual reports and the information, documents and other reports
which are specified in Sections 13 and 15(d) of the Exchange Act. The Company
also shall comply with the other provisions of Section 314(a) of the Trust
Indenture Act.

                                  ARTICLE VIII

              CONSOLIDATION, MERGER, CONVEYANCE, TRANSFER OR LEASE

     Section 8.1 Company May Consolidate, Etc., Only on Certain Terms.

     The Company shall not consolidate with or merge into any other Person or
convey, transfer or lease its properties and assets substantially as an entirety
to any Person, and no Person shall consolidate with or merge into the Company or
convey, transfer or lease its properties and assets substantially as an entirety
to the Company, unless:

     (1) in case the Company shall consolidate with or merge into another Person
or convey, transfer or lease its properties and assets substantially as an
entirety to any Person, the entity formed by such consolidation or into which
the Company is merged or the Person which acquires by conveyance or transfer, or
which leases, the properties and assets of the Company substantially as an
entirety shall be a corporation, partnership or trust and shall expressly
assume, by an indenture supplemental hereto, executed and delivered to the
Trustee, in form satisfactory to the Trustee, the due and punctual payment of
the principal of (and premium, if any) and interest (including any Additional
Interest) on all the Securities and the performance of every covenant of this
Indenture on the part of the Company to be performed or observed;

     (2) immediately after giving effect to such transaction, no Event of
Default, and no event which, after notice or lapse of time, or both, would
become an Event of Default, shall have happened and be continuing;

     (3) in the case of the Securities of a series issued to a ONEOK Capital
Trust, such consolidation, merger, conveyance, transfer or lease is permitted
under the related Trust Agreement and ONEOK Capital Guarantee and does not give
rise to any breach or violation of the related Trust Agreement or ONEOK Capital
Guarantee; and

     (4) the Company has delivered to the Trustee an Officers' Certificate and
an Opinion of Counsel, each stating that such consolidation, merger, conveyance,
transfer or lease and any such supplemental indenture comply with this Article
and that all conditions precedent herein provided relating to such transaction
have been complied with; and the Trustee, subject to Section 6.1, may rely upon
such Officers' Certificate and Opinion of Counsel as conclusive evidence that
such transaction complies with this Section 8.1.

     Section 8.2 Successor Corporation Substituted.

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<PAGE>

     Upon any consolidation or merger by the Company with or into any other
Person, or any conveyance, transfer or lease by the Company of its properties
and assets substantially as an entirety to any Person in accordance with Section
8.1, the successor entity formed by such consolidation or into which the Company
is merged or to which such conveyance, transfer or lease is made shall succeed
to, and be substituted for, and may exercise every right and power of, the
Company, under this Indenture with the same effect as if such successor Person
had been named as the Company herein; and in the event of any such conveyance,
transfer or lease the Company, shall be discharged from all obligations and
covenants under the Indenture and the Securities and may be dissolved and
liquidated.

     Such successor Person may cause to be signed, and may issue either in its
own name or in the name of the Company any or all of the Securities issuable
hereunder which theretofore shall not have been signed by the Company and
delivered to the Trustee; and, upon the order of such successor Person instead
of the Company and subject to all the terms, conditions and limitations in this
Indenture prescribed, the Trustee shall authenticate and shall deliver any
Securities which previously shall have been signed and delivered by the officers
of the Company to the Trustee for authentication pursuant to such provisions and
any Securities which such successor Person thereafter shall cause to be signed
and delivered to the Trustee on its behalf for the purpose pursuant to such
provisions. All the Securities so issued shall in all respects have the same
legal rank and benefit under this Indenture as the Securities theretofore or
thereafter issued in accordance with the terms of this Indenture as though all
of such Securities had been issued at the date of the execution hereof.

     In case of any such consolidation, merger, sale, conveyance or lease, such
changes in phraseology and form may be made in the Securities thereafter to be
issued as may be appropriate.

                                   ARTICLE IX

                             SUPPLEMENTAL INDENTURES

     Section 9.1 Supplemental Indentures without Consent of Holders.

     Without the consent of any Holders, the Company, when authorized by a Board
Resolution, and the Trustee, at any time and from time to time, may amend or
waive any provision of this Indenture or enter into one or more indentures
supplemental hereto, in form satisfactory to the Trustee, for any of the
following purposes:

     (1) to evidence the succession of another Person to the Company, and the
assumption by any such successor of the covenants of the Company herein and in
the Securities contained; or

     (2) to convey, transfer, assign, mortgage or pledge any property to or with
the Trustee or to surrender any right or power herein conferred upon the
Company; or

     (3) to establish the form or terms of Securities of any series as permitted
by Sections 2.1 or 3.1; or

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<PAGE>

     (4) to add to the covenants of the Company for the benefit of the Holders
of all or any series of Securities (and if such covenants are to be for the
benefit of less than all series of Securities, stating that such covenants are
expressly being included solely for the benefit of such series) or to surrender
any right or power herein conferred upon the Company; or

     (5) to add any additional Events of Default for the benefit of the Holders
of all or any series of Securities (and if such additional Events of Default are
to be for the benefit of less than all series of Securities, stating that such
additional Events of Default are expressly being included solely for the benefit
of such series); or

     (6) to change or eliminate any of the provisions of this Indenture,
provided that any such change or elimination shall become effective only when
there is no Security Outstanding of any series created prior to the execution of
such supplemental indenture which is entitled to the benefit of such provision;
or

     (7) to cure any ambiguity, to correct or supplement any provision herein
which may be defective or inconsistent with any other provision herein, or to
make any other provisions with respect to matters or questions arising under
this Indenture, provided that such action pursuant to this clause (7) shall not
adversely affect the interest of the Holders of Securities of any series in any
material respect or, in the case of the Securities of a series issued to a ONEOK
Capital Trust and for so long as any of the corresponding series of Preferred
Securities issued by such ONEOK Capital Trust shall remain outstanding, the
holders of such Preferred Securities; or

     (8) to evidence and provide for the acceptance of appointment hereunder by
a successor Trustee with respect to the Securities of one or more series and
to add to or change any of the provisions of this Indenture as shall be
necessary to provide for or facilitate the administration of the trusts
hereunder by more than one Trustee, pursuant to the requirements of Section
6.11(b); or

     (9) to comply with the requirements of the Commission in order to effect or
maintain the qualification of this Indenture under the Trust Indenture Act.

     Section 9.2 Supplemental Indentures with Consent of Holders.

     With the consent of the Holders of not less than a majority in principal
amount of the Outstanding Securities of each series affected by such
supplemental indenture, by Act of said Holders delivered to the Company and the
Trustee, the Company, when authorized by a Board Resolution, and the Trustee may
enter into an indenture or indentures supplemental hereto for the purpose of
adding any provisions to or changing in any manner or eliminating any of the
provisions of this Indenture or of modifying in any manner the rights of the
Holders of Securities of such series under this Indenture; provided, however,
that no such supplemental indenture shall, without the consent of the Holder of
each Outstanding Security affected thereby,

     (1) except to the extent permitted by Section 3.11 or as otherwise
specified as contemplated by Section 2.1 or Section 3.1 with respect to the
deferral of the payment of interest on the Securities of any series, change the
Stated Maturity of the principal of, or any installment of interest (including
any Additional Interest) on, any Security, or reduce the principal amount
thereof or the rate of interest thereon or reduce any premium payable upon the
redemption

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thereof; or reduce the amount of principal of a Discount Security that would be
due and payable upon a declaration of acceleration of the Maturity thereof
pursuant to Section 5.2, change any obligation of the Company to pay Additional
Sums pursuant to Section 10.6 hereof, or change the place of payment where, or
the coin or currency in which, any Security or interest thereon is payable, or
impair the right to institute suit for the enforcement of any such payment on or
after the Stated Maturity thereof (or, in the case of redemption, on or after
the Redemption Date), or

     (2) reduce the percentage in principal amount of the Outstanding Securities
of any series, the consent of whose Holders is required for any such
supplemental indenture, or the consent of whose Holders is required for any
waiver of compliance with certain provisions of this Indenture or certain
defaults hereunder and their consequences provided for in this Indenture, or

     (3) modify any of the provisions of this Section, Section 5.13 or Section
10.5, except to increase any such percentage or to provide that certain other
provisions of this Indenture cannot be modified or waived without the consent of
the Holder of each Security affected thereby; or

     (4) modify the provisions in Article XIII of this Indenture with respect to
the subordination of Outstanding Securities of any series in a manner adverse to
the Holders thereof;

provided, further, that, in the case of the Securities of a series issued to a
ONEOK Capital Trust, so long as any of the corresponding series of Preferred
Securities issued by such ONEOK Capital Trust remains outstanding, (i) no such
amendment shall be made that adversely affects the holders of such Preferred
Securities in any material respect, and no termination of this Indenture shall
occur, and no waiver of any Event of Default or compliance with any covenant
under this Indenture shall be effective, without the prior consent of the
holders of at least a majority of the aggregate liquidation preference of such
Preferred Securities then outstanding unless and until the principal (and
premium, if any) of the Securities of such series and all accrued and, subject
to Section 3.7, unpaid interest (including any Additional Interest) thereon have
been paid in full and (ii) no amendment shall be made to Section 5.8 of this
Indenture that would impair the rights of the holders of Preferred Securities
provided therein without the prior consent of the holders of each Preferred
Security then outstanding of such series unless and until the principal (and
premium, if any) of the Securities of such series and all accrued and (subject
to Section 3.7) unpaid interest (including any Additional Interest) thereon have
been paid in full.

     A supplemental indenture that changes or eliminates any covenant or other
provision of this Indenture that has expressly been included solely for the
benefit of one or more particular series of Securities or Preferred Securities,
or which modifies the rights of the Holders of Securities or holders of
Preferred Securities of such series with respect to such covenant or other
provision, shall be deemed not to affect the rights under this Indenture of the
Holders of Securities or holders of Preferred Securities of any other series.

     It shall not be necessary for any Act of Holders under this Section to
approve the particular form of any proposed supplemental indenture, but it shall
be sufficient if such Act shall approve the substance thereof.

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     Section 9.3 Execution of Supplemental Indentures.

     In executing or accepting the additional trusts created by any supplemental
indenture permitted by this Article or the modifications thereby of the trusts
created by this Indenture, the Trustee shall be entitled to receive, and
(subject to Section 6.1) shall be fully protected in relying upon, an Officers'
Certificate and an Opinion of Counsel of the Company stating that the execution
of such supplemental indenture is authorized or permitted by this Indenture, and
that all conditions precedent have been complied with. The Trustee may, but
shall not be obligated to, enter into any such supplemental indenture which
affects the Trustee's own rights, duties or immunities under this Indenture or
otherwise.

     Section 9.4 Effect of Supplemental Indentures.

     Upon the execution of any supplemental indenture under this Article, this
Indenture shall be modified in accordance therewith, and such supplemental
indenture shall form a part of this Indenture for all purposes; and every Holder
of Securities theretofore or thereafter authenticated and delivered hereunder
shall be bound thereby.

     Section 9.5 Conformity with Trust Indenture Act.

     Every supplemental indenture executed pursuant to this Article shall
conform to the requirements of the Trust Indenture Act as then in effect.

     Section 9.6 Reference in Securities to Supplemental Indentures.

     Securities authenticated and delivered after the execution of any
supplemental indenture pursuant to this Article may, and shall if required by
the Company, bear a notation in form approved by the Company as to any matter
provided for in such supplemental indenture. If the Company shall so determine,
new Securities of any series so modified as to conform, in the opinion of the
Company, to any such supplemental indenture may be prepared and executed by the
Company and authenticated and delivered by the Trustee in exchange for
Outstanding Securities of such series.

                                    ARTICLE X

                                    COVENANTS

     Section 10.1 Payment of Principal, Premium and Interest.

     The Company covenants and agrees for the benefit of the Holders of each
series of Securities that it will duly and punctually pay the principal of (and
premium, if any) and interest (including any Additional Interest) and any other
amounts payable on the Securities of that series in accordance with the terms of
such Securities and this Indenture. Whenever in this Indenture or the Securities
there is a reference in any context to the payment of interest on the
Securities, such mention shall be deemed to include payments of Additional
Interest to the extent that Additional Interest is payable on the Securities.
Express mention of the payment of Additional Interest (if applicable) in any
provisions hereof shall not be construed as excluding Additional Interest in
those provisions hereof where such express mention is not made.

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     Section 10.2 Maintenance of Office or Agency.

     The Company will maintain in each Place of Payment for any series of
Securities, an office or agency where Securities of that series may be presented
or surrendered for payment and an office or agency where Securities of that
series may be surrendered for transfer or exchange and where notices and demands
to or upon the Company in respect of the Securities of that series and this
Indenture may be served. The Company initially appoints the Trustee, acting
through its Corporate Trust Office, as its agent for said purposes. The Company
will give prompt written notice to the Trustee of any change in the location of
any such office or agency. If at any time the Company shall fail to maintain
such office or agency or shall fail to furnish the Trustee with the address
thereof; such presentations, surrenders, notices and demands may be made or
served at the Corporate Trust Office of the Trustee, and the Company hereby
appoints the Trustee as its agent to receive all such presentations, surrenders,
notices and demands.

     The Company may also from time to time designate one or more other offices
or agencies where the Securities may be presented or surrendered for any or all
of such purposes, and may from time to time rescind such designations; provided,
however, that no such designation or rescission shall in any manner relieve the
Company of its obligation to maintain an office or agency in each Place of
Payment for Securities of any series for such purposes. The Company will give
prompt written notice to the Trustee of any such designation and any change in
the location of any such office or agency.

     Section 10.3 Money or Security Payments to be Held in Trust.

     If the Company shall at any time act as its own Paying Agent with respect
to any series of Securities, it will, on or before each due date of the
principal of (and premium, if any) or interest (including any Additional
Interest) on any of the Securities of such series, segregate and hold in trust
for the benefit of the Persons entitled thereto a sum sufficient to pay the
principal (and premium, if any) or interest (including any Additional Interest)
so becoming due until such sums shall be paid to such Persons or otherwise
disposed of as herein provided, and will promptly notify the Trustee of its
failure so to act.

     Whenever the Company shall have one or more Paying Agents, it will, prior
to 10:00 a.m. New York City time on each due date of the principal of (and
premium, if any) or interest (including any Additional Interest) on any
Securities, deposit with a Paying Agent a sum sufficient to pay the principal
(and premium, if any) or interest (including any Additional Interest) so
becoming due, such sum to be held in trust for the benefit of the Persons
entitled to such principal and premium (if any) or interest (including any
Additional Interest), and (unless such Paying Agent is the Trustee) the Company
will promptly notify the Trustee of its failure so to act.

     The Company will cause each Paying Agent other than the Trustee to execute
and deliver to the Trustee an instrument in which such Paying Agent shall agree
with the Trustee, subject to the provisions of this Section, that such Paying
Agent will:

     (1) hold all sums held by it for the payment of the principal of (and
premium, if any) or interest (including any Additional Interest) on Securities
in trust for the benefit of the Persons

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entitled thereto until such sums shall be paid to such Persons or otherwise
disposed of as herein provided;

     (2) give the Trustee notice of any default by the Company (or any other
obligor upon the Securities) in the making of any payment of principal (and
premium, if any) or interest (including any Additional Interest);

     (3) at any time during the continuance of any such default, upon the
written request of the Trustee, forthwith pay to the Trustee all sums so held in
trust by such Paying Agent; and

     (4) comply with the provisions of the Trust Indenture Act applicable to it
as a Paying Agent.

     The Company may at any time, for the purpose of obtaining the satisfaction
and discharge of this Indenture or for any other purpose, pay, or by Company
Order direct any Paying Agent to pay, to the Trustee all sums held in trust by
the Company or such Paying Agent, such sums to be held by the Trustee upon the
same terms as those upon which such sums were held by the Company or such Paying
Agent; and, upon such payment by any Paying Agent to the Trustee, such Paying
Agent shall be released from all further liability with respect to such money.

     Any money deposited with the Trustee or any Paying Agent, or then held by
the Company, in trust for the payment of the principal of (and premium, if any)
or interest (including any Additional Interest) on any Security and remaining
unclaimed for two years after such principal (and premium, if any) or interest
(including any Additional Interest) has become due and payable shall (unless
otherwise required by mandatory provision of applicable escheat or abandoned or
unclaimed property law) be paid on Company Request to the Company, or (if then
held by the Company) shall (unless otherwise required by mandatory provision of
applicable escheat or abandoned or unclaimed property law) be discharged from
such trust; and the Holder of such Security shall thereafter, as an unsecured
general creditor, look only to the Company for payment thereof; and all
liability of the Trustee or such Paying Agent with respect to such trust money,
and all liability of the Company as trustee thereof; shall thereupon cease;
provided, however, that the Trustee or such Paying Agent, before being required
to make any such repayment, may at the expense of the Company cause to be
published once, in a newspaper published in the English language, customarily
published on each Business Day and of general circulation in the Borough of
Manhattan, The City of New York, notice that such money remains unclaimed and
that, after a date specified therein, which shall not be less than 30 days from
the date of such publication, any unclaimed balance of such money then remaining
will be repaid to the Company.

     Section 10.4 Statement as to Compliance.

     The Company shall deliver to the Trustee, within 120 days after the end of
each calendar year ending after the date hereof; an Officers' Certificate
complying with Section 314(a)(4) of the Trust Indenture Act and covering the
preceding calendar year, stating whether or not to the best knowledge of the
signers thereof of the Company is in default in the performance, observance or
fulfillment of or compliance with any of the terms, provisions, covenants and

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<PAGE>

conditions of this Indenture, and if the Company shall be in default, specifying
all such defaults and the nature and status thereof of which they may have
knowledge. For the purpose of this Section 10.4, compliance shall be determined
without regard to any grace period or requirement of notice provided pursuant to
the terms of this Indenture.

     Section 10.5 Waiver of Certain Covenants.

     Subject to the rights of holders of Preferred Securities specified in
Section 9.2, if any, the Company may omit in any particular instance to comply
with any covenant or condition provided pursuant to Section 3.1, 9.1(3) or
9.1(4) with respect to the Securities of any series, if before or after the time
for such compliance the Holders of at least a majority in principal amount of
the Outstanding Securities of such series shall, by Act of such Holders, either
waive such compliance in such instance or generally waive compliance with such
covenant or condition, but no such waiver shall extend to or affect such
covenant or condition except to the extent so expressly waived, and, until such
waiver shall become effective, the obligations of the Company in respect of any
such covenant or condition shall remain in full force and effect.

     Section 10.6 Additional Sums.

     In the case of the Securities of a series issued to a ONEOK Capital Trust,
so long as no Event of Default has occurred and is continuing and except as
otherwise specified as contemplated by Section 2.1 or Section 3.1, in the event
that (i) a ONEOK Capital Trust is the Holder of all of the Outstanding
Securities of such series, (ii) a Tax Event in respect of such ONEOK Capital
Trust shall have occurred and be continuing and (iii) the Company shall not have
(A) redeemed the Securities of such series pursuant to Section 11.7(b) or (B)
terminated such ONEOK Capital Trust pursuant to Section 9.2(b) of the related
Trust Agreement, the Company shall pay to such ONEOK Capital Trust (and its
permitted successors or assigns under the related Trust Agreement) for so long
as such ONEOK Capital Trust (or its permitted successor or assignee) is the
registered holder of any Securities of such series, such additional amounts as
may be necessary in order that the amount of Distributions (including any
Additional Amounts (as defined in such Trust Agreement)) then due and payable by
such ONEOK Capital Trust on the related Preferred Securities and Common
Securities that at any time remain outstanding in accordance with the terms
thereof shall not be reduced as a result of any Additional Taxes (the
"Additional Sums"). Whenever in this Indenture or the Securities there is a
reference in any context to the payment of principal of, premium, if any, or
interest on the Securities, such mention shall be deemed to include mention of
the payments of the Additional Sums provided for in this paragraph to the extent
that, in such context, Additional Sums are, were or would be payable in respect
thereof pursuant to the provisions of this paragraph and express mention of the
payment of Additional Sums (if applicable) in any provisions hereof shall not be
construed as excluding Additional Sums in those provisions hereof where such
express mention is not made; provided, however, that the deferral of the payment
of interest pursuant to Section 3.11 or the Securities shall not defer the
payment of any Additional Sums that may be due and payable.

     Section 10.7 Additional Covenants.

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         The Company covenants and agrees with each Holder of Securities of each
series that it shall not, (a) declare or pay any dividends or distributions on,
or redeem purchase, acquire or make a liquidation payment with respect to, any
shares of the its capital stock, or (b) make any payment of principal of or
interest or premium, if any, on or repay, repurchase or redeem any debt
securities issued by it that rank pari passu with or junior in interest to the
Securities of such series or make any guarantee payments with respect to any
guarantee by the Company of debt securities of any Subsidiary of the Company if
such guarantee ranks pari passu with or junior in interest to the Securities
(other than (a) repurchases, redemptions or other acquisitions of shares of
capital stock of the Company in connection with any employment contract, benefit
plan or other similar arrangement with or for the benefit of any one or more
employees, officers, directors or consultants, in connection with a dividend
reinvestment or stockholder stock purchase plan or in connection with the
issuance of capital stock of the Company (or securities convertible into or
exercisable for such capital stock) as consideration in an acquisition
transaction entered into prior to the applicable Extension Period or other event
referred to below, (b) as a result of an exchange or conversion of any class or
series of the Company's capital stock (or any capital stock of a Subsidiary of
the Company) for any class or series of the Company's capital stock or of any
class or series of the Company's indebtedness for any class or series of the
Company's capital stock, (c) the purchase of fractional interests in shares of
the Company's capital stock pursuant to the conversion or exchange provisions of
such capital stock or the security being converted or exchanged, (d) any
declaration of a dividend in connection with any Rights Plan, or the issuance of
rights, stock or other property under any Rights Plan, or the redemption or
repurchase of rights pursuant thereto, or (e) any dividend in the form of stock,
warrants, options or other rights where the dividend stock or the stock issuable
upon exercise of such warrants, options or other rights is the same stock as
that on which the dividend is being paid or ranks pari passu with or junior to
such stock), if at such time (i) there shall have occurred any event of which
the Company has actual knowledge that (A) with the giving of notice or the lapse
of time or both, would constitute an Event of Default with respect to the
Securities of such series and (B) in respect of which the Company shall have not
taken reasonable steps to cure, (ii) if the Securities of such series are held
by a ONEOK Capital Trust, the Company shall be in default with respect to its
payment of any obligations under the ONEOK Capital Guarantee relating to the
Preferred Securities issued by such ONEOK Capital Trust or (iii) the Company
shall have given notice of its election to begin an Extension Period with
respect to the Securities of such series as provided herein and shall not have
rescinded such notice, or such Extension Period, or any extension thereof, shall
be continuing.

         The Company also covenants with each Holder of Securities of a series
issued to a ONEOK Capital Trust (i) to maintain directly or indirectly 100%
ownership of the Common Securities of such ONEOK Capital Trust; provided,
however, that any permitted successor of the Company hereunder may succeed to
the Company's ownership of such Common Securities, (ii) not to voluntarily
terminate, wind-up or liquidate such ONEOK Capital Trust, except (a) in
connection with a distribution of the Securities of such series to the holders
of Preferred Securities in liquidation of such ONEOK Capital Trust or (b) in
connection with certain mergers, consolidations or amalgamations permitted by
the related Trust Agreement and (iii) to use its reasonable efforts, consistent
with the terms and provisions of such Trust Agreement, to cause such ONEOK
Capital Trust to remain classified as a grantor trust and not an association
taxable as a corporation for United States federal income tax purposes.

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                                   ARTICLE XI

                            REDEMPTION OF SECURITIES

         Section 11.1  Applicability of This Article.

         Redemption of Securities of any series (whether by operation of a
sinking fund or otherwise) as permitted or required by any form of Security
issued pursuant to this Indenture shall be made in accordance with such form of
Security and this Article; provided, however, that if any provision of any such
form of Security shall conflict with any provision of this Article, the
provision of such form of Security shall govern. Except as otherwise set forth
in the form of Security of a particular series, each Security of such series
which is redeemed in part shall be subject to redemption only in the amount of
$25 or integral multiples thereof.

         Section 11.2  Election to Redeem; Notice to Trustee.

         The election of the Company to redeem any Securities shall be evidenced
by or pursuant to a Board Resolution. In case of any redemption at the election
of the Company of less than all of the Securities of any particular series and
having the same terms, the Company shall, not less than 30 nor more than 60 days
prior to the Redemption Date (unless a shorter notice shall be satisfactory to
the Trustee), notify the Trustee of such date and of the principal amount of
Securities of that series to be redeemed. In the case of any redemption of
Securities prior to the expiration of any restriction on such redemption
provided in the terms of such Securities, the Company shall furnish the Trustee
with an Officers' Certificate and an Opinion of Counsel evidencing compliance
with such restriction.

         Section 11.3  Selection of Securities to be Redeemed.

         If less than all the Securities of any series are to be redeemed
(unless all the Securities of such series and of a specified tenor are to be
redeemed or unless such redemption affects only a single Security), the
particular Securities to be redeemed shall be selected not more than 60 days
prior to the Redemption Date by the Trustee, from the Outstanding Securities of
such series not previously called for redemption, by such method as the Trustee
shall deem fair and appropriate and which may provide for the selection for
redemption of a portion of the principal amount of any Security of such series,
provided that the unredeemed portion of the principal amount of any Security
shall be in an authorized denomination (which shall not be less than the minimum
authorized denomination) for such Security. If less than all the Securities of
such series and of a specified tenor are to be redeemed (unless such redemption
affects only a single Security), the particular Securities to be redeemed shall
be selected not more than 60 days prior to the Redemption Date by the Trustee,
from the Outstanding Securities of such series and specified tenor not
previously called for redemption in accordance with the preceding sentence.

         The Trustee shall promptly notify the Company in writing of the
Securities selected for partial redemption and the principal amount thereof to
be redeemed. For all purposes of this Indenture, unless the context otherwise
requires, all provisions relating to the redemption of Securities shall relate,
in the case of any Security redeemed or to be redeemed only in part, to the
portion of the principal amount of such Security which has been or is to be
redeemed. If the

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Company shall so direct, Securities registered in the name of the Company, any
Affiliate or any Subsidiary thereof shall not be included in the Securities
selected for redemption.

         Section 11.4  Notice of Redemption.

         Notice of redemption shall be given by first-class mail, postage
prepaid, mailed not later than the thirtieth day, and not earlier than the
sixtieth day, prior to the Redemption Date, to each Holder of Securities to be
redeemed, at the address of such Holder as it appears in the Securities
Register.

         With respect to Securities of each series to be redeemed, each notice
of redemption shall state:

         (a) the Redemption Date;

         (b) the Redemption Price or, if the Redemption Price cannot be
calculated prior to the time the notice is required to be sent, the estimate of
the Redemption price provided pursuant to the Indenture together with a
statement that it is an estimate and that the actual Redemption Price will be
calculated on the third Business Day prior to the Redemption Date (if such an
estimate of the Redemption Price is given, a subsequent notice shall be given as
set forth above setting forth the Redemption Price promptly following the
calculation thereof);

         (c) if less than all Outstanding Securities of such particular series
and having the same terms are to be redeemed, the identification (and, in the
case of partial redemption, the respective principal amounts) of the particular
Securities to be redeemed;

         (d) that on the Redemption Date, the Redemption Price will become due
and payable upon each such Security or portion thereof; and that interest
thereon, if any, shall cease to accrue on and after said date;

         (e) the place or places where such Securities are to be surrendered for
payment of the Redemption Price;

         (f) such other provisions as may be required in respect of the terms of
the Securities; and

         (g) that the redemption is for a sinking fund, if such is the case.

         Notice of redemption of Securities to be redeemed at the election of
the Company shall be given by the Company or, at the Company's request, by the
Trustee in the name and at the expense of the Company and shall not be
revocable. The notice if mailed in the manner herein provided shall be
conclusively presumed to have been duly given, whether or not the Holder
receives such notice. In any case, a failure to give such notice by mail or any
defect in the notice to the Holder of any Security designated for redemption as
a whole or in part shall not affect the validity of the proceedings for the
redemption of any other Security.

         Section 11.5  Deposit of Redemption Price.

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         Prior to 10:00 a.m. New York City time on the Redemption Date specified
in the notice of redemption given as provided in Section 11.4, the Company will
deposit with the Trustee or with one or more Paying Agents (or if the Company is
acting as its own Paying Agent, the Company will segregate and hold in trust as
provided in Section 10.3) an amount of money sufficient to pay the Redemption
Price of; and any accrued interest (including any Additional Interest) on, all
the Securities (or portions thereof) that are to be redeemed on that date.

         Section 11.6  Payment of Securities Called for Redemption.

         If any notice of redemption has been given as provided in Section 11.4,
the Securities or portion of Securities with respect to which such notice has
been given shall become due and payable on the date and at the place or places
stated in such notice at the applicable Redemption Price together with accrued
interest (including any Additional Interest) to the Redemption Date. On
presentation and surrender of such Securities duly endorsed or accompanied by
written instruments of transfer execute by the Holder or its duly authorized
attorney, in form satisfactory to the Company, the Trustee and the Securities
Registrar, at a Place of Payment in said notice specified, the said securities
or the specified portions thereof shall be paid and redeemed by the Company at
the applicable Redemption Price, together with accrued interest (including any
Additional Interest) to the Redemption Date; provided, however, that, unless
otherwise specified as contemplated by Section 3.1, installments of interest
(including any Additional Interest) whose Stated Maturity is on or prior to the
Redemption Date will be payable to the Holders of such Securities, or one or
more Predecessor Securities, registered as such at the close of business on the
relevant Record Dates according to their terms and the provisions of Section
3.7.

         Upon presentation of any Security redeemed in part only, duly endorsed
or accompanied by written instruments of transfer execute by the Holder or its
duly authorized attorney, in form satisfactory to the Company, the Trustee and
the Securities Registrar, the Company shall execute and the Trustee shall
authenticate and deliver to the Holder thereof, at the expense of the Company, a
new Security or Securities of the same series, of authorized denominations, in
aggregate principal amount equal to the unredeemed portion of the Security so
presented and having the same Original Issue Date, Stated Maturity and terms. If
a Global Security is so surrendered, such new Security will also be a new Global
Security.

         Unless the Company fails to deposit or pay the Redemption Price,
together with accrued interest (including any Additional Interest), upon the
Redemption Date the Securities to be redeemed shall no longer be Outstanding and
no interest (including any Additional Interest) shall accrue thereon, and upon
receipt of any certification representing the redeemed Securities shall be
cancelled as provided in Section 13.9. If any Security called for redemption
shall not be so paid upon surrender thereof for redemption, the principal of and
premium, if any, on such Security shall, until paid, bear interest from the
Redemption Date at the rate prescribed therefor in the Security.

         Section 11.7  Right of Redemption of Securities Initially Issued to a
ONEOK Capital Trust.

         In the case of the Securities of a series initially issued to a ONEOK
Capital Trust, except as otherwise specified as contemplated by Section 3.1, the
Company, at its option, may redeem

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such Securities (i) on or after the date five years after the Original Issue
Date of such Securities, in whole at any time or in part from time to time, or
(ii) upon the occurrence and during the continuation of a Special Event, at any
time within 90 days following the occurrence of such Special Event in respect of
such ONEOK Capital Trust, in whole (but not in part), in each case at a
Redemption Price equal to 100% of the principal amount thereof.

         If less than all the Securities of any such series are to be redeemed,
the aggregate principal amount of such Securities remaining Outstanding after
giving effect to such redemption shall be sufficient to satisfy any provisions
of the Trust Agreement related to each ONEOK Trust to which such Securities were
issued, including any requirement in the applicable Trust Agreement as to the
minimum liquidation amount, if any, of Preferred Securities that may be held by
a holder under such Trust Agreement.

                                  ARTICLE XII

                                  SINKING FUNDS

         Section 12.1  Applicability of Article.

         The provisions of this Article shall be applicable to any sinking fund
for the retirement of Securities of any series except as otherwise specified as
contemplated by Section 3.1 for such Securities.

         The minimum amount of any sinking fund payment provided for by the
terms of any Securities of any series is herein referred to as a "mandatory
sinking fund payment", and any sinking fund payment in excess of such minimum
amount which is permitted to be made by the terms of such Securities of any
series is herein referred to as an "optional sinking fund payment". If provided
for by the terms of any Securities of any series, the cash amount of any sinking
fund payment may be subject to reduction as provided in Section 12.2. Each
sinking fund payment shall be applied to the redemption of Securities of any
series as provided for by the terms of such Securities.

         Section 12.2  Satisfaction of Sinking Fund Payments with Securities.

         In lieu of making all or any part of a mandatory sinking fund payment
with respect to any Securities of a series in cash, the Company may at its
option, at any time no more than 16 months and no less than 30 days prior to the
date on which such sinking fund payment is due, deliver to the Trustee
Securities of such series (together with the unmatured coupons, if any,
appertaining thereto) theretofore purchased or otherwise acquired by the
Company, or credit securities previously canceled or otherwise delivered to the
Trustee for cancellation, except Securities of such series that have been
redeemed through the application of mandatory or optional sinking fund payments
pursuant to the terms of the Securities of such series, accompanied by a Company
Order instructing the Trustee to cancel such Securities if not previously
canceled or credit such obligations and stating that the Securities of such
series were originally issued by the Company by way of bona fide sale or other
negotiation for value; provided that the Securities to be so credited have not
been previously so credited. The Securities to be so credited shall be received
and credited for such purpose by the Trustee at the

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Redemption Price for such Securities, as specified in the Securities so to be
redeemed, for redemption through operation of the sinking fund and the amount of
such sinking fund payment shall be reduced accordingly.

         Section 12.3  Redemption of Securities for Sinking Fund.

         Not less than 60 days prior to each sinking fund payment date for any
series of Securities, the Company will deliver to the Trustee an Officers'
Certificate specifying the amount of the next ensuing sinking fund payment for
such Securities pursuant to the terms of such Securities, the portion thereof;
if any, which is to be satisfied by payment of cash in the currency in which the
Securities of such series are payable (except as provided pursuant to Section
3.1) and the portion thereof; if any, which is to be satisfied by delivering and
crediting Securities pursuant to Section 12.2 and will also deliver to the
Trustee any Securities to be so delivered. Such Officers' Certificate shall be
irrevocable and upon its delivery the Company shall be obligated to make the
cash payment or payments therein referred to, if any, on or before the
succeeding sinking fund payment date. In the case of the failure of the Company
to deliver such Officers' Certificate (or, as required by this Indenture, the
Securities and coupons, if any, specified in such Officers' Certificate), the
sinking fund payment due on the succeeding sinking fund payment date for such
series shall be paid entirely in cash and shall be sufficient to redeem the
principal amount of the Securities of such series subject to a mandatory sinking
fund payment without the right to deliver or credit securities as provided in
Section 12.2 and without the right to make the optional sinking fund payment
with respect to such series at such time.

         Any sinking fund payment or payments (mandatory or optional) made in
cash plus any unused balance of any preceding sinking fund payments made with
respect to the Securities of any particular series shall be applied by the
Trustee (or by the Company if the Company is acting as its own Paying Agent) on
the sinking fund payment date on which such payment is made (or, if such payment
is made before a sinking fund payment date, on the sinking fund payment date
immediately following the date of such payment) to the redemption of Securities
of such series at the Redemption Price specified in such Securities with respect
to the sinking fund. Any sinking fund moneys not so applied or allocated by the
Trustee (or, if the Company is acting as its own Paying Agent, segregated and
held in trust by the Company as provided in Section 10.3) for such series and
together with such payment (or such amount so segregated) shall be applied in
accordance with the provisions of this Section 12.3. Any and all sinking fund
moneys with respect to the Securities of any particular series held by the
Trustee (or if the Company is acting as its own Paying Agent, segregated and
held in trust as provided in Section 10.3) on the last sinking fund payment date
with respect to Securities of such series and not held for the payment or
redemption of particular Securities of such series shall be applied by the
Trustee (or by the Company if the Company is acting as its own Paying Agent),
together with other moneys, if necessary, to be deposited (or segregated)
sufficient for the purpose, to the payment of the principal of the Securities of
such series at Maturity. The Trustee shall select the Securities to be redeemed
upon such sinking fund payment date in the manner specified in Section 11.3 and
cause notice of the redemption thereof to be given in the name of and at the
expense of the Company in the manner provided in Section 11.4. Such notice
having been duly given, the redemption of such Securities shall be made upon the
terms and in the manner stated in Section 11.6. On or before each sinking fund
payment date, the Company shall pay to the Trustee (or, if the Company is acting
as its own Paying Agent, the Company shall segregate and

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hold in trust as provided in Section 10.3) in cash a sum in the currency in
which Securities of such series are payable (except as provided pursuant to
Section 3.1) equal to the principal and any interest accrued to the Redemption
Date for Securities or portions thereof to be redeemed on such sinking fund
payment date pursuant to this Section 12.3.

         Neither the Trustee nor the Company shall redeem any Securities of a
series with sinking fund moneys or mail any notice of redemption of Securities
of such series by operation of the sinking fund for such series during the
continuance of a default in payment of interest, if any, on any Securities of
such series or of any Event of Default (other than an Event of Default occurring
as a consequence of this paragraph) with respect to the Securities of such
series, except that if the notice of redemption shall have been provided in
accordance with the provisions hereof; the Trustee (or the Company, if the
Company is then acting as its own Paying Agent) shall redeem such Securities if
cash sufficient for that purpose shall be deposited with the Trustee (or
segregated by the Company) for that purpose in accordance with the terms of this
Article XII. Except as aforesaid, any moneys in the sinking fund for such series
at the time when any such default or Event of Default shall occur and any moneys
thereafter paid into such sinking fund shall, during the continuance of such
default or Event of Default, be held as security for the payment of the
Securities and coupons, if any, of such series; provided, however, that in case
such default or Event of Default shall have been cured or waived herein, such
moneys shall thereafter be applied on the next sinking fund payment date for the
Securities of such series on which such moneys may be applied pursuant to the
provisions of this Section 12.3.

                                  ARTICLE XIII

                           SUBORDINATION OF SECURITIES

         Section 13.1  Securities Subordinate to Senior Debt.

         The Company covenants and agrees, and each Holder of a Security, by its
acceptance thereof, likewise covenants and agrees, that, to the extent and in
the manner hereinafter set forth in this Article, the payment of the principal
of (and premium, if any) and interest (including any
         Additional Interest) on each and all of the Securities are hereby
expressly made subordinate and subject in right of payment to the prior payment
in full of all Senior Debt of the Company.

         Section 13.2  Payment Over of Proceeds Upon Dissolution, Etc.

         In case of the pendency of any receivership, insolvency, liquidation,
bankruptcy, reorganization, arrangement, adjustment, composition or other
judicial proceeding relative to the Company (each such event, if any, herein
sometimes referred to as a "Proceeding"), then the holders of Senior Debt of the
Company shall be entitled to receive payment in full of all Allocable Amounts of
such Senior Debt, or provision shall be made for such payment before the Holders
of the Securities are entitled to receive or retain any payment or distribution
of any kind or character, whether in cash, property or securities (including any
payment or distribution which may be payable or deliverable by reason of the
payment of any other Debt of the Company (including any series of the
Securities) subordinated to the payment of the Securities, such payment or
distribution being hereinafter referred to as a "Junior Subordinated Payment"),
on account of principal of (or premium, if any) or interest (including any
Additional Interest) on the

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Securities or on account of the purchase or other acquisition of Securities by
the Company and to that end the holders of Senior Debt of the Company shall be
entitled to receive, for application to the payment thereof; any payment or
distribution of any kind or character, whether in cash, property or securities,
including any Junior Subordinated Payment, which may be payable or deliverable
in respect of the Securities in any such Proceeding.

         In the event that, notwithstanding the foregoing provisions of this
Section, the Trustee or the Holder of any Security shall have received any
payment or distribution of assets of the Company of any kind or character,
whether in cash, property or securities, including any Junior Subordinated
Payment, before all Allocable Amounts of all Senior Debt of the Company are paid
in full or payment thereof is provided for, and if such fact shall, at or prior
to the time of such payment or distribution, have been made known to the Trustee
or, as the case may be, such Holder, then and in such event such payment or
distribution shall be paid over or delivered forthwith to the trustee in
bankruptcy, receiver, liquidating trustee, custodian, assignee, agent or other
Person making payment or distribution of assets of the Company for application
to the payment of all Allocable Amounts of all Senior Debt of the Company
remaining unpaid, to the extent necessary to pay all Allocable Amounts of all
Senior Debt of the Company in full, after giving effect to any concurrent
payment or distribution to or for the holders of Senior Debt of the Company.

         For purposes of this Article only, the words "any payment or
distribution of any kind or character, whether in cash, property or securities"
shall not be deemed to include shares of stock of the Company as reorganized or
readjusted, or securities of the Company or any other corporation provided for
by a plan of reorganization or readjustment which securities are subordinated in
right of payment to all then outstanding Senior Debt of the Company to
substantially the same extent as the Securities are so subordinated as provided
in this Article. The consolidation of the Company with, or the merger of the
Company into, another Person or the liquidation or dissolution of the Company
following the sale of all or substantially all of its properties and assets as
an entirety to another Person upon the terms and conditions set forth in Article
VIII shall not be deemed a Proceeding for the purposes of this Section if the
Person formed by such consolidation or into which the Company is merged or the
Person which acquires by sale such properties and assets as an entirety, as the
case may be, shall, as a part of such consolidation, merger, or sale comply with
the conditions set forth in Article VIII.

         Section 13.3  Prior Payment to Senior Debt Upon Acceleration of
Securities.

         In the event that any Securities are declared due and payable before
their Stated Maturity, then and in such event the holders of the Senior Debt of
the Company outstanding at the time such Securities so become due and payable
shall be entitled to receive payment in full of all Allocable Amounts due on or
in respect of such Senior Debt (including any amounts due upon acceleration),
before the Holders of the Securities are entitled to receive any payment or
distribution of any kind or character, whether in cash, properties or securities
(including any Junior Subordinated Payment) by the Company on account of the
principal of (or premium, if any) or interest (including any Additional
Interest) on the Securities or on account of the purchase or other acquisition
of Securities by the Company; provided, however, that nothing in this Section
shall prevent the satisfaction of any sinking fund payment in accordance with
this Indenture or as otherwise specified as contemplated by Section 3.1 for the
Securities of any

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series by delivering and crediting pursuant to Section 12.2 or as otherwise
specified as contemplated by Section 3.1 for the Securities of any series
Securities which have been acquired (upon redemption or otherwise) prior to such
declaration of acceleration.

         In the event that, notwithstanding the foregoing, the Company shall
make any payment to the Trustee or the Holder of any Security prohibited by the
foregoing provisions of this Section, and if such fact shall, at or prior to the
time of such payment, have been made known to the Trustee or, as the case may
be, such Holder, then and in such event such payment shall be paid over and
delivered forthwith to the Company.

         The provisions of this Section shall not apply to any payment with
respect to which Section 13.2 would be applicable.

         Section 13.4  No Payment When Senior Debt in Default.

         (a) Upon the maturity of any Senior Debt by lapse of time, acceleration
(unless waived, rescinded or annulled) or otherwise, or upon any payment default
(with or without the giving of notice or lapse of time or both, in accordance
with the terms of the instrument governing such Senior Debt, and without any
waiver or forgiveness) with respect to any Senior Debt, all amounts payable
thereon shall first be paid in full, on such Senior Debt, before any payment is
made, directly or indirectly by set off or otherwise, on account of principal
of, or interest on, the Securities of such series or to acquire any of the
Securities of such series or on account of the redemption provisions of the
Securities of such series.

         (b) In the event and during the continuation of any default on any
Senior Debt of the Company, or in the event that any event of default with
respect to any Senior Debt of the Company shall have occurred and be continuing
and shall have resulted in such Senior Debt becoming or being declared due and
payable prior to the date on which it would otherwise have become due and
payable, unless and until such event of default shall have been cured or waived
or shall have ceased to exist and such acceleration shall have been rescinded or
annulled, or (b) in the event any judicial proceeding shall be pending with
respect to any such default or such event or default, then, upon written notice
thereof given to the Trustee by or on behalf of the holders of any such Senior
Debt ("Default Notice"), no payment or distribution of any kind or character,
whether in cash, properties or securities (including any Junior Subordinated
Payment) shall be made by the Company on account of principal of (or premium, if
any) or interest (including any Additional Interest), if any, on the Securities
or on account of the purchase or other acquisition of Securities by the Company;
provided, however, that this paragraph (b) shall not prevent the making of any
payment (which is not otherwise prohibited by paragraph (a)) for more than 179
days after the Default Notice shall have been given unless the Senior Debt in
respect of which such event of default exists has been declared due and payable
in its entirety, in which case no such payment may be made until such
acceleration has been rescinded or annulled or such Senior Debt has been paid in
full; further provided, that nothing in this Section shall prevent the
satisfaction of any sinking fund payment in accordance with this Indenture or as
otherwise specified as contemplated by Section 3.1 for the Securities of any
series by delivering and crediting pursuant to Section 12.2 or as otherwise
specified as contemplated by Section 3.1 for the Securities of any series
Securities which have been acquired (upon redemption or otherwise) prior to such
default or event of default.

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         In the event that, notwithstanding the foregoing, the Company shall
make any payment to the Trustee or the Holder of any Security prohibited by the
foregoing provisions of this Section, and if such fact shall, at or prior to the
time of such payment, have been made known to the Trustee or, as the case may
be, such Holder, then and in such event such payment shall be paid over and
delivered forthwith to the Company.

         The provisions of this Section shall not apply to any payment with
respect to which Section 13.2 would be applicable.

         Section 13.5  Payment Permitted If No Default.

         Nothing contained in this Article or elsewhere in this Indenture or in
any of the Securities shall prevent (a) the Company at any time except during
the pendency of any Proceeding with respect to it referred to in Section 13.2 or
under the conditions described in Sections 13.3 and 13.4, from making payments
at any time of principal of (and premium, if any) or interest (including
Additional Interest) on the Securities or (b) the application by the Trustee of
any money deposited with it hereunder to the payment of or on account of the
principal of (and premium, if any) or interest (including any Additional
Interest) on the Securities or the retention of such payment by the Holders, if,
at the time of such application by the Trustee, it did not have knowledge
through receipt of notice by a Responsible Officer of Trustee three Business
Days prior to making such payment that such payment would have been prohibited
by the provisions of this Article.

         Section 13.6  Subrogation to Rights of Holders of Senior Debt.

         Subject to the payment in full of all amounts due or to become due on
all Senior Debt of the Company or the provision for such payment in cash or cash
equivalents or otherwise in a manner satisfactory to the holders of Senior Debt
of the Company the Holders of the Securities shall be subrogated to the extent
of the payments or distributions made to the holders of such Senior Debt
pursuant to the provisions of this Article (equally and ratably with the holders
of all indebtedness of the Company which by its express terms is subordinated to
Senior Debt of the Company to substantially the same extent as the Securities
are subordinated to the Senior Debt of the Company and is entitled to like
rights of subrogation by reason of any payments or distributions made to holders
of such Senior Debt) to the rights of the holders of such Senior Debt to receive
payments and distributions of cash, property and securities applicable to the
Senior Debt of the Company until the principal of (and premium, if any) and
interest on the Securities shall be paid in full. For purposes of such
subrogation, no payments or distributions to the holders of the Senior Debt of
the Company of any cash, property or securities to which the Holders of the
Securities or the Trustee would be entitled except for the provisions of this
Article, and no payments over pursuant to the provisions of this Article to the
holders of Senior Debt of the Company by Holders of the Securities or the
Trustee, shall, as among the Company its creditors other than holders of its
Senior Debt, and the Holders of the Securities, be deemed to be a payment or
distribution by the Company to or on account of its Senior Debt.

         Section 13.7  Provisions Solely to Define Relative Rights.

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     The provisions of this Article are and are intended solely for the purpose
of defining the relative rights of the Holders of the Securities on the one hand
and the holders of Senior Debt of the Company on the other hand. Nothing
contained in this Article or elsewhere in this Indenture or in the Securities is
intended to or shall (a) impair, as between the Company and the Holders of the
Securities, the obligations of the Company, which are absolute and
unconditional, to pay to the Holders of the Securities the principal of (and
premium, if any) and interest (including any Additional Interest) on the
Securities as and when the same shall become due and payable in accordance with
their terms; or (b) affect the relative rights against the Company of the
Holders of the Securities and creditors of the Company other than their rights
in relation to the holders of Senior Debt of the Company; or (c) prevent the
Trustee or the Holder of any Security from exercising all remedies otherwise
permitted by applicable law upon default under this Indenture including, without
limitation, filing and voting claims in any Proceeding with respect to the
Company subject to the rights, if any, under this Article of the holders of
Senior Debt with respect to the Company to receive cash, property and securities
otherwise payable or deliverable to the Trustee or such Holder.

     Section 13.8 Trustee to Effectuate Subordination.

     Each Holder of a Security by his or her acceptance thereof authorizes and
directs the Trustee on his or her behalf to take such action as may be necessary
or appropriate to acknowledge or effectuate the subordination provided in this
Article and appoints the Trustee his or her attorney-in-fact for any and all
such purposes.

     Section 13.9 No Waiver of Subordination Provisions.

     No right of any present or future holder of any Senior Debt with respect to
the Company to enforce subordination as herein provided shall at any time in any
way be prejudiced or impaired by any act or failure to act on the part of the
Company or by any act or failure to act, in good faith, by any such holder, or
by any noncompliance by the Company with the terms, provisions and covenants of
this Indenture, regardless of any knowledge thereof that any such holder may
have or be otherwise charged with.

     Without in any way limiting the generality of the immediately preceding
paragraph, the holders of Senior Debt with respect to the Company may, at any
time and from to time, without the consent of or notice to the Trustee or the
Holders of the Securities, without incurring responsibility to the Holders of
the Securities and without impairing or releasing the subordination provided in
this Article or the obligations hereunder of the Holders of the Securities to
the holders of such Senior Debt, do any one or more of the following: (i) change
the manner, place or terms of payment or extend the time of payment of, or renew
or alter, Senior Debt with respect to the Company or otherwise amend or
supplement in any manner Senior Debt with respect to the Company or any
instrument evidencing the same or any agreement under which Senior Debt with
respect to the Company is outstanding; (ii) sell, exchange, release or otherwise
deal with any property pledged, mortgaged or otherwise securing Senior Debt with
respect to the Company; (iii) release any Person liable in any manner for the
collection of Senior Debt with respect to the Company; and (iv) exercise or
refrain from exercising any rights against the Company and any other Person.

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     Section 13.10 Notice to Trustee.

     The Company shall give prompt written notice to a Responsible Officer of
the Trustee of any fact known to it which would prohibit the making of any
payment to or by the Trustee in respect of the Securities. Notwithstanding the
provisions of this Article or any other provision of this Indenture, the Trustee
shall not be charged with knowledge of the existence of any facts which would
prohibit the making of any payment to or by the Trustee in respect of the
Securities, unless and until a Responsible Officer of the Trustee shall have
received written notice thereof from the Company or a holder of Senior Debt
thereof or from any trustee, agent or representative therefor; provided,
however, that if the Trustee shall not have received the notice provided for in
this Section at least three Business Days prior to the date upon which by the
terms hereof any monies may become payable for any purpose (including, without
limitation, the payment of the principal of (and premium, if any) or interest
(including any Additional Interest) on any Security), then, anything herein
contained to the contrary notwithstanding, the Trustee shall have full power and
authority to receive such monies and to apply the same to the purpose for which
they were received and shall not be affected by any notice to the contrary which
may be received by it within three Business Days prior to such date.

     Subject to the provisions of Section 6.1, the Trustee shall be entitled to
rely on the delivery to it of a written notice by a Person representing himself
to be a holder of Senior Debt of the Company, (or a trustee therefor) to
establish that such notice has been given by a holder of Senior Debt of the
Company, (or a trustee therefor). In the event that the Trustee determines in
good faith that further evidence is required with respect to the right of any
Person as a holder of Senior Debt of the Company to participate in any payment
or distribution pursuant to this Article, the Trustee may request such Person to
furnish evidence to the reasonable satisfaction of the Trustee as to the amount
of Senior Debt of the Company held by such Person, the extent to which such
Person is entitled to participate in such payment or distribution and any other
facts pertinent to the rights of such Person under this Article, and if such
evidence is not furnished, the Trustee may defer any payment to such Person
pending judicial determination as to the right of such Person to receive such
payment.

     Section 13.11 Reliance on Judicial Order or Certificate of Liquidating
Agent.

     Upon any payment or distribution of assets of the Company referred to in
this Article, the Trustee, subject to the provisions of Section 6.1, and the
Holders of the Securities shall be entitled to rely upon any order or decree
entered by any court of competent jurisdiction in which such Proceeding is
pending, or a certificate of the trustee in bankruptcy, receiver, conservator,
liquidating trustee, custodian, assignee for the benefit of creditors, agent or
other Person making such payment or distribution, delivered to the Trustee or to
the Holders of Securities, for the purpose of ascertaining the Persons entitled
to participate in such payment or distribution, the holders of the Senior Debt
and other indebtedness of the Company the amount thereof or payable thereon, the
amount or amounts paid or distributed thereon and all other facts pertinent
thereto or to this Article.

     Section 13.12 Trustee Not Fiduciary for Holders of Senior Debt.

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     The Trustee, in its capacity as trustee under this Indenture, shall not be
deemed to owe any fiduciary duty to the holders of Senior Debt of the Company
and shall not be liable to any such holders if it shall in good faith mistakenly
pay over or distribute to Holders of Securities or to the Company, or to any
other Person cash, property or securities to which any holders of Senior Debt of
the Company shall be entitled by virtue of this Article or otherwise.

     Section 13.13 Rights of Trustee as Holder of Senior Debt; Preservation of
Trustee's Rights.

     The Trustee in its individual capacity shall be entitled to all the rights
set forth in this Article with respect to any Senior Debt of the Company which
may at any time be held by it, to the same extent as any other holder of such
Senior Debt, and nothing in this Indenture shall deprive the Trustee of any of
its rights as such holder. Nothing in this Article shall be construed to apply
to claims of the Trustee or any predecessor Trustee under Section 5.6 or 6.7.

     Section 13.14 Article Applicable to Paying Agents.

     In case at any time any Paying Agent other than the Trustee shall have been
appointed by the Company and be then acting hereunder, the term "Trustee" as
used in this Article shall in such case (unless the context otherwise requires)
be construed as extending to and including such Paying Agent within its meaning
as fully for all intents and purposes as if such Paying Agent were named in this
Article in addition to or in place of the Trustee.

     Section 13.15 Certain Conversions or Exchanges Deemed Payment.

     For the purposes of this Article only, (a) the issuance and delivery of
junior securities upon conversion or exchange of Securities shall not be deemed
to constitute a payment or distribution on account of the principal of (or
premium, if any) or interest (including any Additional Interest) on Securities
or on account of the purchase or other acquisition of Securities, and (b) the
payment, issuance or delivery of cash, property or securities (other than junior
securities) upon conversion or exchange of a Security shall be deemed to
constitute payment on account of the principal of such security. For the
purposes of this Section, the term "junior securities" means (i) shares of any
stock of any class of the Company and (ii) securities of the Company which are
subordinated in right of payment to all Senior Debt thereof which may be
outstanding at the time of issuance or delivery of such securities to
substantially the same extent as, or to a greater extent than, the Securities
are so subordinated as provided in this Article.

                                     * * * *

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     This instrument may be executed in any number of counterparts, each of
which so executed shall be deemed to be an original, but all such counterparts
shall together constitute but one and the same instrument.

     IN WITNESS WHEREOF, the parties hereto have caused this Indenture to be
duly executed, and their respective corporate seals to be hereunto affixed and
attested, all as of the day and year first above written.

ONEOK, INC.


___________________________________
By:

Attest:

___________________________________


___________________________________
SUNTRUST BANK,

as Trustee


___________________________________
By:


Attest:

___________________________________

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