Exhibit 4(b)

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                          SUPPLEMENTAL INDENTURE NO. 6
                             _____________________

                          TUCSON ELECTRIC POWER COMPANY

                                       TO

                              THE BANK OF NEW YORK,

                                     TRUSTEE
                             _____________________

                             Dated as of May 1, 2005


            Supplemental to Indenture of Mortgage and Deed of Trust,
                          dated as of December 1, 1992

                             _____________________


                      Creating A Series of Bonds Designated
                   Second Mortgage Bonds, Collateral Series E

                             _____________________

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This instrument constitutes a mortgage, a deed of trustand a security agreement.


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     SUPPLEMENTAL INDENTURE NO. 6, dated as of May 1, 2005, between TUCSON
ELECTRIC POWER COMPANY (hereinafter sometimes called the "Company"), a
corporation organized and existing under the laws of the State of Arizona,
having its principal office at One South Church Avenue, in the City of Tucson,
Arizona, as trustor, and THE BANK OF NEW YORK (successor in trust to Bank of
Montreal Trust Company), a banking corporation organized and existing under the
laws of the State of New York and having its principal office at 101 Barclay
Street, in the Borough of Manhattan, The City of New York, New York, as trustee
(hereinafter sometimes called the "Trustee"), under the Indenture of Mortgage
and Deed of Trust, dated as of December 1, 1992 (hereinafter called the
"Original Indenture"), as heretofore amended and supplemented, this Supplemental
Indenture No. 6 being supplemental thereto (the Original Indenture as heretofore
amended and supplemented, and as supplemented hereby, and as it may from time to
time be further supplemented, modified, altered or amended by any supplemental
indenture entered into in accordance with and pursuant to the provisions
thereof, is hereinafter called the "Indenture").

                             RECITALS OF THE COMPANY

     WHEREAS, the Original Indenture was authorized, executed and delivered by
the Company to provide for the issuance from time to time of its Bonds (such
term and all other capitalized terms used herein without definition having the
meanings assigned to them in the Original Indenture), to be issued in one or
more series as therein contemplated, and to provide security for the payment of
the principal of and premium, if any, and interest, if any, on the Bonds; and

     WHEREAS, the Company proposes to establish a series of Bonds designated
"Second Mortgage Bonds, Collateral Series E" and to be limited in aggregate
principal amount (except as contemplated in clause (b) of Section 2 of Article
II of the Original Indenture) to $400,600,000, such series of Bonds and such
Bonds to be hereinafter sometimes called, respectively, "Series 6" and "Series 6
Bonds"; and

     WHEREAS, all acts and proceedings required by law and by the articles of
incorporation and by-laws of the Company, including all action requisite on the
part of its shareholders, directors and officers, necessary to make the Series 6
Bonds, when executed by the Company, authenticated and delivered by the Trustee
and duly issued, the valid, binding and legal obligations of the Company, and to
constitute this Supplemental Indenture a valid, binding and legal instrument, in
accordance with its and their terms, have been done and taken; and the execution
and delivery of this Supplemental Indenture No. 6 have been in all respects duly
authorized; and

     WHEREAS, effective June 3, 1999, The Bank of New York succeeded to all of
the corporate trust business of Bank of Montreal Trust Company, and, as a
consequence, The Bank of New York, being otherwise qualified and eligible under
Article XII of the Original Indenture, became the successor trustee under the
Indenture without further act on the part of the parties thereto, as
contemplated by Section 11 of Article XII of the Original Indenture.


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                                GRANTING CLAUSES

     NOW, THEREFORE, THIS SUPPLEMENTAL INDENTURE NO. 6 WITNESSETH, that, in
order to secure the payment of the principal of and premium, if any, and
interest, if any, on all Bonds at any time Outstanding under the Indenture
according to their tenor, purport and effect, and to secure the performance and
observance of all the covenants and conditions therein and herein contained
(except any covenant of the Company with respect to the refund or reimbursement
of taxes, assessments or other governmental charges on account of the ownership
of the Bonds of any series or the income derived therefrom, for which the
Holders of the Bonds shall look only to the Company and not to the property
hereby mortgaged or pledged), and to declare the terms and conditions upon and
subject to which the Series 6 Bonds are to be issued, and for and in
consideration of the premises and of the mutual covenants herein contained and
of the purchase and acceptance of the Bonds by the Holders thereof, and of the
sum of $1 duly paid to the Company by the Trustee at or before the ensealing and
delivery hereof, and for other good and valuable consideration, the receipt and
sufficiency whereof are hereby acknowledged, the Company has executed and
delivered this Supplemental Indenture No. 6, and by these presents does grant,
bargain, sell, release, convey, assign, transfer, mortgage, pledge, set over and
confirm unto the Trustee, and grant to the Trustee a security interest in:

     All and singular the premises, property, assets, rights and franchises of
the Company (except Excepted Property), whether now or hereafter owned,
constructed or acquired, of whatever character and wherever situated including,
among other things (but reference to or enumeration of any particular kinds,
classes or items of property shall not be deemed to exclude from the operation
and effect of this Supplemental Indenture No. 6 any kind, class or item not so
referred to or enumerated), all right, title and interest of the Company in and
to the property described as granted in "Schedule A" attached to this
Supplemental Indenture No. 6 and made part of these Granting Clauses to the same
extent as if fully set forth in the same, and all plants for the generation of
electricity by water, steam and/or other power; all power houses, substations,
transmission lines, and distributing systems; all offices, buildings and
structures, and the equipment thereof; all machinery, engines, boilers, dynamos,
machines, regulators, meters, transformers, generators and motors; all
appliances whether electrical, gas or mechanical, conduits, cables and lines;
all pipes, service pipes, fittings, valves and connections, poles, wires, tools,
implements, apparatus, furniture, and chattels; all municipal franchises and
other franchises; all lines for the transmission and/or distribution of electric
current, including towers, poles, wires, cables, pipes, conduits, street
lighting systems and all apparatus for use in connection therewith; all real
estate, lands, and leaseholds; all easements, servitudes, licenses, permits,
rights, powers, franchises, privileges, rights-of-way and other rights in or
relating to real estate or the occupancy of the same and all the right, title
and interest of the Company in and to all other property of any kind or nature
appertaining to and/or used and/or occupied and/or enjoyed in connection with
any property hereinbefore described; it being the intention of the parties that
all property of every kind, real, personal or mixed (including, but not limited
to, all property of the types hereinbefore described), other than Excepted
Property, which may be acquired by the Company after the date hereof, shall,
immediately upon the acquisition thereof by the Company, to the extent of such
acquisition, and without any further conveyance or assignment, become and be
subject to the direct lien of the Indenture as fully and completely as though
now owned by the Company and described in said "Schedule A"; it further being
the intention of the parties, however, that the lien of and security interest
granted by this Supplemental Indenture No. 6 shall not result in the Trustee


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having greater rights with respect to any property of the Company, real,
personal or mixed (including, but not limited to, leasehold interests in
property), than the rights of the Company with respect to such property.

     TOGETHER WITH all and singular the tenements, hereditaments and
appurtenances belonging or in any wise appertaining to the aforesaid premises,
property, assets, rights and franchises or any part thereof, with the reversion
and reversions, remainder and remainders, and all the estate, right, title and
interest and claim whatsoever, at law as well as in equity, which the Company
now has or may hereafter acquire in and to the aforesaid premises, property,
assets, rights and franchises and every part and parcel thereof.

     Subject, however, to the reservations, exceptions, limitations and
restrictions contained in the several deeds, leases, servitudes, contracts,
decrees, judgments, or other instruments through which the Company acquired or
claims title to or enjoys the use of the aforesaid properties; and subject also
to such easements, leases, reservations, servitudes, reversions and other rights
and privileges of others and such mortgages, liens and other encumbrances in,
on, over, across or through said properties as existed at the time of the
acquisition of such properties by the Company or as have been granted by the
Company to other persons at or prior to the time of the issuance and delivery of
the Bonds of the Initial Series, including, but not limited to, the lien of the
1941 Mortgage and the security interest created thereby; and subject also to
Permitted Encumbrances and, as to any property acquired by the Company after the
time of the issuance and delivery of the Bonds of the Initial Series, to any
easements, leases, reservations, servitudes, reversions and other rights and
privileges of others and mortgages, liens or other encumbrances thereon
existing, and to any mortgages, liens and other encumbrances for unpaid portions
of the purchase money placed thereon, at the time of such acquisition, it being
understood that with respect to any such after-acquired property the Lien of the
Indenture shall at all times be junior, subject and subordinate to the lien of
the 1941 Mortgage and the security interest created thereby; and subject also to
the provisions of Article XI of the Original Indenture;

     TO HAVE AND TO HOLD the Trust Estate and all and singular the lands,
properties, estates, rights, franchises, privileges and appurtenances hereby
granted, bargained, sold, released, conveyed, assigned, transferred, mortgaged,
pledged, set over and confirmed, together with all the appurtenances thereunto
appertaining, unto the Trustee and its successors and assigns, forever;

     BUT IN TRUST, NEVERTHELESS, for the equal and proportionate use, benefit,
security and protection of those who from time to time shall hold the Bonds
authenticated and delivered hereunder and under the Indenture and duly issued by
the Company, without any discrimination, preference or priority of any one Bond
over any other by reason of priority in the time of issue, sale or negotiation
thereof or otherwise, except as provided in Section 2 of Article IV of the
Original Indenture, so that, subject to said provisions, each and all of said
Bonds shall have the same right, lien and privilege under the Indenture and
shall be equally secured thereby (except as any sinking, amortization,
improvement, renewal or other fund, established in accordance with the
provisions of the Indenture, may afford additional security for the Bonds of any
particular series), and shall have the same proportionate interest and share in
the Trust Estate, with the same effect as if all of the Bonds had been issued,
sold and negotiated simultaneously on the date of the delivery hereof; and in
trust for enforcing payment of the principal of the Bonds, and premium, if any,


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and interest, if any, thereon, according to the tenor, purport and effect of the
Bonds and of the Indenture, and for enforcing the terms, provisions, covenants
and agreements herein, in the Indenture and in the Bonds set forth;

     UPON CONDITION that, until the happening of a Default, the Company shall be
suffered and permitted to possess, use and enjoy the Trust Estate (except money,
securities and other personal property pledged or deposited with or required to
be pledged or deposited with the Trustee hereunder or under the Indenture) and
to receive and use the rents, issues, income, revenues, earnings and profits
therefrom, all as more specifically provided in Section 1 of Article VII of the
Original Indenture;

     AND UPON THE TRUSTS, USES AND PURPOSES and subject to the covenants,
agreements and conditions hereinafter set forth and declared.

                                    ARTICLE I

                             ADDITIONAL DEFINITIONS

     SECTION 1. APPLICABILITY OF ARTICLE

     For all purposes of this Supplemental Indenture No. 6, except as otherwise
expressly provided or unless the context otherwise requires, the terms defined
in this Article shall have the meanings herein specified and include the plural
as well as the singular.

     SECTION 2. ADDITIONAL DEFINITIONS.

     "ADMINISTRATIVE AGENT" means Union Bank of California, N.A., in its
capacity as Administrative Agent under the Credit Agreement.

     "CREDIT AGREEMENT" means the Credit Agreement, dated as of May 4, 2005,
among the Company, the Lenders party thereto, the Issuing Banks party thereto,
the Syndication Agent party thereto, the Documentation Agent party thereto and
Union Bank of California, N.A., as Administrative Agent, as amended,
supplemented or otherwise modified from time to time.

     "INTEREST PAYMENT DATE" means the last day of each March, June, September
and December; provided, however, that the first Interest Payment Date shall be
June 30, 2005.

     "MATURITY" means the date on which the principal of the Series 6 Bonds
becomes due and payable, whether at stated maturity, upon redemption or
acceleration, or otherwise.

     The following terms shall have the meanings specified in the Credit
Agreement: "AGGREGATE COMMITMENT", "ALTERNATE BASE RATE", "ISSUING BANK",
"LETTER OF CREDIT", "LOANS" AND "OBLIGATIONS".

     A copy of the Credit Agreement is filed at the office of the Administrative
Agent at 445 South Figueroa Street, 15th floor, Los Angeles, California 90071
and at the office of the Company at One South Church Avenue, Tucson, Arizona
85701.


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                                   ARTICLE II

                                 SERIES 6 BONDS

     There is hereby established a series of Bonds having the following terms
and characteristics (the lettered subdivisions set forth below corresponding to
the lettered subdivisions of Section 2 of Article II of the Indenture):

          (a) the title of the Bonds of such series shall be "Second Mortgage
     Bonds, Collateral Series E" (such Bonds being hereinafter sometimes called
     the "Series 6 Bonds");

          (b) the aggregate principal amount of Series 6 Bonds which may be
     authenticated and delivered under the Indenture shall be limited to
     $400,600,000, except as contemplated in subdivision (b) of Section 2 of
     Article II of the Original Indenture;

          (c) not applicable;

          (d) the Series 6 Bonds shall mature on June 30, 2012;

          (e) during the period from and including the date of the first
     authentication and delivery of the Series 6 Bonds to and including the day
     next preceding the first Interest Payment Date, the Series 6 Bonds shall
     bear interest at the rate of ten per centum (10%) per annum; thereafter,
     the Series 6 Bonds shall bear interest at a rate equal to the Alternate
     Base Rate from time to time in effect plus 500 basis points; interest on
     the Series 6 Bonds shall accrue from and including the date of the first
     authentication and delivery of the Series 6 Bonds, except as otherwise
     provided in the form of bond attached hereto as Exhibit A; interest on the
     Series 6 Bonds shall be payable on each Interest Payment Date and at
     Maturity, and the Regular Record Date for the interest payable on each
     Interest Payment Date shall be the day next preceding such Interest Payment
     Date; interest payable at Maturity shall be paid to the Person to whom
     principal shall be paid; and interest on the Series 6 Bonds during any
     period for which payment is made shall be computed in accordance with the
     Credit Agreement;

          (f) the office of the Trustee in New York, New York, shall be the
     office or agency of the Company in The City of New York where (i) the
     principal of the Series 6 Bonds and interest payable thereon at Maturity
     shall be payable upon presentation thereof, (ii) notices, presentations and
     demands to or upon the Company in respect of the Series 6 Bonds or the
     Indenture may be served or made and (iii) Series 6 Bonds may be surrendered
     for registration of transfer or exchange; the principal office of the
     Company in Tucson, Arizona shall be an additional financial office or
     agency where the principal of the Series 6 Bonds and interest payable
     thereon at Maturity shall be payable upon presentation thereof; interest
     payable on the Series 6 Bonds prior to Maturity shall be paid by the
     Company directly to the Holders thereof.

          (g) the Series 6 Bonds shall not be redeemable, in whole or in part,
     at the option of the Company;


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          (h) upon (i) the occurrence of an Event of Default under the Credit
     Agreement, and further upon the condition that, in accordance with the
     terms of the Credit Agreement, the Aggregate Commitments shall have been or
     shall have terminated and the Loans shall have been declared to be or shall
     have otherwise become due and payable immediately and the Administrative
     Agent shall have delivered to the Company a notice demanding redemption of
     the Series 6 Bonds which notice states that it is being delivered pursuant
     to Article VII of the Credit Agreement or (ii) the occurrence of an Event
     of Default under clause (h) or (i) of Article VII of the Credit Agreement,
     then all Series 6 Bonds shall be redeemed immediately at the principal
     amount thereof plus accrued interest to the date of redemption;

          (i) the Series 6 Bonds shall be issued in denominations of $1,000 and
     any amount in excess thereof;

          (j) not applicable;

          (k) not applicable;

          (l) not applicable;

          (m) not applicable;

          (n) no service charge shall be made for the registration of transfer
     or exchange of Series 6 Bonds;

          (o) (i) the Series 6 Bonds are to be issued and delivered to the
     Administrative Agent in order to provide collateral security for the
     obligation of the Company under the Credit Agreement to pay the
     Obligations, to the extent and subject to the limitations set forth in
     clauses (ii) and (iii) of this subdivision.

              (ii) the obligation of the Company to pay interest on the Series
          6 Bonds on any Interest Payment Date prior to Maturity (x) shall be
          deemed to have been satisfied and discharged in full in the event that
          all amounts then due in respect of the Obligations shall have been
          paid or (y) shall be deemed to remain unsatisfied in an amount equal
          to the aggregate amount then due in respect of the Obligations and
          remaining unpaid (not in excess, however, of the amount otherwise then
          due in respect of interest on the Series 6 Bonds).

              (iii) the obligation of the Company to pay the principal of and
          accrued interest on the Series 6 Bonds at or after Maturity (x) shall
          be deemed to have been satisfied and discharged in full in the event
          that all amounts then due in respect of the Obligations shall have
          been paid and no Letter of Credit shall remain outstanding or (y)
          shall be deemed to remain unsatisfied in an amount equal to the
          aggregate amount then due in respect of the Obligations and remaining
          unpaid plus the aggregate stated amount of the outstanding Letters of
          Credit (not in excess, however, of the amount otherwise then due in
          respect of principal of and accrued interest on the Series 6 Bonds).


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              (iv) the Trustee shall be entitled to presume that the obligation
          of the Company to pay the principal of and interest on the Series 6
          Bonds as the same shall become due and payable shall have been fully
          satisfied and discharged unless and until it shall have received a
          written notice from the Administrative Agent, signed by an authorized
          officer thereof, stating that the principal of and/or interest on the
          Series 6 Bonds has become due and payable and has not been fully paid,
          and specifying the amount of funds required to make such payment;

          (p) in the event of an application by the Administrative Agent for
     payment or for a substituted Series 6 Bond pursuant to Section 11 of
     Article II of the Original Indenture, the Administrative Agent shall not be
     required to provide any indemnity or pay any expenses or charges as
     contemplated in said Section 11; and

          (q) the Series 6 Bonds shall have such other terms as are set forth in
     the form of bond attached hereto as Exhibit A, which form is hereby
     designated as the form of the Series 6 Bonds.

                                   ARTICLE III

                            MISCELLANEOUS PROVISIONS

     This Supplemental Indenture No. 6 is a supplement to the Original
Indenture. As heretofore supplemented and further supplemented by this
Supplemental Indenture No. 6, the Original Indenture is in all respects
ratified, approved and confirmed, and the Original Indenture as heretofore
supplemented and this Supplemental Indenture No. 6 shall together constitute one
and the same instrument.

     The Trustee makes no representation as to the validity or sufficiency of
this Supplemental Indenture No. 6. The statements and recitals herein are deemed
to be those of the Company and not of the Trustee.


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     IN WITNESS WHEREOF, Tucson Electric Power Company has caused its corporate
name to be hereunto affixed, and this instrument to be signed by one of its Vice
Presidents, and its corporate seal to be hereunto affixed and attested by one of
its Assistant Secretaries for and on its behalf; and The Bank of New York, as
trustee, in evidence of its acceptance of the trust hereby created, has caused
its corporate name to be hereunto affixed, and this instrument to be signed by
one of its authorized signatories and its corporate seal to be hereunto affixed
and attested by one of its authorized signatories, for and on its behalf, all as
of the day and year first above written.

                                           TUCSON ELECTRIC POWER COMPANY


                                           By /s/Kevin P. Larson
                                             ---------------------------
                                             Vice President

Attest:


/s/Linda Kennedy
-------------------
Assistant Secretary


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                                           THE BANK OF NEW YORK,
                                           Trustee


                                           By /s/Patricia Gallagher
                                             ---------------------------
                                             Authorized Signatory

Attest:


/s/Jeremy Finkelstein
---------------------
Authorized Signatory


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STATE OF ARIZONA      )
                      ) ss.:
COUNTY OF PIMA        )

     This instrument was acknowledged before me this 28th day of April 2005 by
Kevin P. Larson, as Vice President, and Linda Kennedy, as Assistant Secretary,
of TUCSON ELECTRIC POWER COMPANY, an Arizona corporation, known to me to be the
individuals who executed this instrument, and known to me to be a Vice President
and an Assistant Secretary, respectively, of said corporation, and who
personally acknowledged before me and stated that they executed said instrument
on behalf of said corporation for the purposes and consideration therein
expressed.

                                          /s/Diana K. Durako
                                           -----------------------------
                                           NOTARY PUBLIC


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STATE OF NEW YORK     )
                      ) ss.:
COUNTY OF NEW YORK    )

     This instrument was acknowledged before me this 27th day of April 2005 by
Patricia Gallagher, as Authorized Signatory, and Jeremy Finkelstein, as
Authorized Signatory, of THE BANK OF NEW YORK, a New York banking corporation,
known to me to be the individuals who executed this instrument, and known to me
to be Authorized Signatories of said corporation, and who personally
acknowledged before me and stated that they executed said instrument on behalf
of said corporation for the purposes and consideration therein expressed.


                                           /s/Joseph A. Lloret
                                           -----------------------------
                                           NOTARY PUBLIC


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                                                                       EXHIBIT A

                                 [Form of Bond]
                         This bond is non-transferable,
              except to a successor Administrative Agent under the
                      Credit Agreement referred to herein.

No. ________________                                                  $_________

                          TUCSON ELECTRIC POWER COMPANY

                    SECOND MORTGAGE BOND, COLLATERAL SERIES E

                                DUE JUNE 30, 2012

     TUCSON ELECTRIC POWER COMPANY, a corporation of the State of Arizona
(hereinafter sometimes called the "Company"), for value received, promises to
pay to

as Administrative Agent under the Credit Agreement hereinafter referred to or
registered assigns, the principal sum of

                                                                         DOLLARS

on June 30, 2012 in coin or currency of the United States of America which at
the time of payment shall be legal tender for the payment of public and private
debts, at the office or agency of the Company in The City of New York, or in the
City of Tucson, Arizona, upon presentation hereof, and quarterly, on March 31,
June 30, September 30 and December 31 in each year, commencing June 30, 2005
(each an "Interest Payment Date"), and at Maturity (as defined in Supplemental
Indenture No. 6 hereinafter referred to), to pay interest thereon in like coin
or currency at the rate specified below, from the Interest Payment Date next
preceding the date of this bond (unless this bond be dated on an Interest
Payment Date, in which case from the date hereof; or unless this bond be dated
prior to the first Interest Payment Date, in which case from and including the
date of the first authentication and delivery of the bonds of this series),
until the Company's obligation with respect to such principal sum shall be
discharged.

     During the period from and including the date of the first authentication
and delivery of the bonds of this series to and including the day next preceding
the first Interest Payment Date, the bonds of this series shall bear interest at
the rate of ten per centum (10%) per annum; thereafter, the bonds of this series
shall bear interest at a rate equal to the Alternate Base Rate (as defined in
Supplemental Indenture No. 6 hereinafter referred to) from time to time in
effect plus 500 basis points. Interest on the bonds of this series during any
period for which payment is made shall be computed in accordance with the Credit
Agreement.

     This bond is one of an issue of bonds of the Company, issued and to be
issued in one or more series under and equally and ratably secured (except as
any sinking, amortization, improvement, renewal or other fund, established in
accordance with the provisions of the indenture hereinafter mentioned, may


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afford additional security for the bonds of any particular series) by the
Indenture of Mortgage and Deed of Trust, dated as of December 1, 1992 (the
"Original Indenture"), from the Company to The Bank of New York (successor in
trust to Bank of Montreal Trust Company), as trustee (the "Trustee"), as
supplemented by six supplemental indentures including Supplemental Indenture No.
6, dated as of May 1, 2005 (the Original Indenture, as so supplemented, and such
Supplemental Indenture being hereinafter called the "Indenture" and
"Supplemental Indenture No. 6", respectively), to which Indenture reference is
hereby made for a description of the property mortgaged and pledged, the nature
and extent of the security provided by the Indenture, the rights and limitations
of rights of the Company, the Trustee and the holders of said bonds with respect
to the security provided by the Indenture, the powers, duties and immunities of
the Trustee, the terms and conditions upon which such bonds are and are to be
secured, and the circumstances under which additional bonds may be issued. The
acceptance of this bond shall be deemed to constitute the consent and agreement
by the holder hereof to all of the terms and provisions of the Indenture. This
bond is one of a series of bonds designated as the Second Mortgage Bonds,
Collateral Series E, of the Company.

     The Indenture permits, with certain exceptions as therein provided, the
Trustee to enter into one or more supplemental indentures for the purpose of
adding any provisions to, or changing in any manner or eliminating any of the
provisions of, the Indenture with the consent of the holders of not less than
sixty per centum (60%) in aggregate principal amount of the bonds of all series
then outstanding under the Indenture, considered as one class; provided,
however, that if there shall be bonds of more than one series outstanding under
the Indenture and if a proposed supplemental indenture shall directly affect the
rights of the holders of bonds of one or more, but less than all, of such
series, then the consent only of the holders of bonds in aggregate principal
amount of the outstanding bonds of all series so directly affected, considered
as one class, shall be required; and provided, further, that if the bonds of any
series shall have been issued in more than one tranche and if the proposed
supplemental indenture shall directly affect the rights of the holder of bonds
of one or more, but less than all, of such tranches, then the consent only of
the holders of bonds in aggregate principal amount of the outstanding bonds of
all tranches so directly affected, considered as one class, shall be required;
and provided, further, that the Indenture permits the Trustee to enter into one
or more supplemental indentures for limited purposes without the consent of any
holders of bonds. Any such consent by the holder of this bond shall be
conclusive and binding upon such holder and upon all future holders of this bond
and of any bond issued upon the registration of transfer hereof or in exchange
therefor or in lieu hereof, whether or not notation of such consent is made upon
this bond.

     The Company has issued and delivered the bonds of this series to Union Bank
of California, N.A., as Administrative Agent (the "Administrative Agent") under
the Credit Agreement, dated as of May 4, 2005, among the Company, the Lenders
party thereto, the Issuing Banks party thereto, the Syndication Agent party
thereto, the Documentation Agent party thereto and Union Bank of California,
N.A., as Administrative Agent, as amended, supplemented or otherwise modified
from time to time (the "Credit Agreement"), in order to provide collateral
security for the obligation of the Company thereunder to pay the Obligations (as
defined in Supplemental Indenture No. 6).

     Upon the occurrence of an Event of Default under the Credit Agreement, and
further upon such additional conditions as are set forth in subdivision (h) of
Article II of Supplemental Indenture No. 6, then all bonds of this series shall


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be redeemed immediately at the principal amount thereof plus accrued interest to
the date of redemption.

     The obligation of the Company to pay interest on the bonds of this series
on any Interest Payment Date prior to Maturity (a) shall be deemed to have been
satisfied and discharged in full in the event that all amounts then due in
respect of the Obligations shall have been paid or (b) shall be deemed to remain
unsatisfied in an amount equal to the aggregate amount then due in respect of
the Obligations and remaining unpaid (not in excess, however, of the amount
otherwise then due in respect of interest on the bonds of this series).

     The obligation of the Company to pay the principal of and accrued interest
on the bonds of this series at or after Maturity (x) shall be deemed to have
been satisfied and discharged in full in the event that all amounts then due in
respect of the Obligations shall have been paid and no Letter of Credit (as
defined in Supplemental Indenture No. 6) shall remain outstanding or (y) shall
be deemed to remain unsatisfied in an amount equal to the aggregate amount then
due in respect of the Obligations and remaining unpaid plus the aggregate stated
amount of the outstanding Letters of Credit (not in excess, however, of the
amount otherwise then due in respect of principal of and accrued interest on the
bonds of this series).

     The principal of this bond and the interest accrued hereon may become or be
declared due and payable before the stated maturity hereof, on the conditions,
in the manner and at the times set forth in the Indenture, upon the happening of
a default as therein provided.

     This bond is non-transferable except as required to effect transfer to any
successor administrative agent under the Credit Agreement, any such transfer to
be made at the office or agency of the Company in The City of New York, upon
surrender and cancellation of this bond, and upon any such transfer a new bond
of this series, for the same aggregate principal amount and having the same
stated maturity date, will be issued to the transferee in exchange herefor.
Prior to due presentment for registration of transfer, the Company and the
Trustee may deem and treat the person in whose name this bond is registered as
the absolute owner hereof for the purpose of receiving payment and for all other
purposes. This bond, alone or with other bonds of this series, may in like
manner be exchanged at such office or agency for one or more bonds of this
series of the same aggregate principal amount and having the same stated
maturity date and interest rate, all as provided in the Indenture.

     No recourse shall be had for the payment of the principal of or interest on
this bond, or for any claim based hereon or otherwise in respect hereof or of
the Indenture, against any incorporator, shareholder, director or officer, as
such, past, present or future, of the Company or of any predecessor or successor
corporation, either directly or through the Company or any predecessor or
successor corporation, whether by virtue of any constitution, statute or rule of
law, or by the enforcement of any assessment or penalty or by any legal or
equitable proceeding or otherwise howsoever (including, without limiting the
generality of the foregoing, any proceeding to enforce any claimed liability of
shareholders of the Company, based upon any theory of disregarding the corporate
entity of the Company or upon any theory that the Company was acting as the
agent or instrumentality of the shareholders); all such liability being, by the
acceptance hereof and as a part of the consideration for the issuance hereof,
expressly waived and released by every holder hereof, and being likewise waived


                                       A-3
<PAGE>


and released by the terms of the Indenture under which this bond is issued, as
more fully provided in said Indenture.

     This bond shall not be valid or become obligatory for any purpose until the
certificate of authentication hereon shall have been signed by The Bank of New
York, or its successor, as Trustee under the Indenture.


                                       A-4
<PAGE>


     IN WITNESS WHEREOF, the Company has caused this bond to be signed in its
name by the manual or facsimile signature of its President or one of its Vice
Presidents, and its corporate seal, or a facsimile thereof, to be impressed or
imprinted hereon and attested by the manual or facsimile signature of its
Secretary or one of its Assistant Secretaries.

     Dated: May __, 2005

                                           TUCSON ELECTRIC POWER COMPANY

                                           By:
                                              --------------------------

Attest:

----------------------


                                       A-5
<PAGE>


                [FORM OF TRUSTEE'S CERTIFICATE OF AUTHENTICATION]

     This is one of the bonds, of the series designated therein, described in
the within-mentioned Indenture.

Dated:  May __, 2005

                                           The Bank of New York,
                                             Trustee

                                           By:
                                              --------------------------


                                       A-6
<PAGE>


                                                                      SCHEDULE A


                        DESCRIPTION OF MORTGAGED PROPERTY

                               GENERIC DESCRIPTION

          All electric generating plants, gas generating plant, gas holders,
steam plant, gas regulating stations, substations and other properties of the
Company, including all power houses, transmission lines, buildings, pipes,
structures and works, and the lands of the Company on which the same are
situated, and all the Company's lands, easements, rights, rights-of-way, water
rights, rights to the use of water, including all of the Company's right, title
and interest in and to any and all decrees therefor, permits, franchises,
consents, privileges, licenses, poles, towers, wires, switch racks, insulators,
pipes, machinery, engines, boilers, motors, regulators, meters, tools,
appliances, equipment, appurtenances and supplies, forming a part of or
appertaining to said plants, holders, sites, stations or other properties, or
any of them, or used or enjoyed or capable of being used or enjoyed in
conjunction or connection therewith; and

          All electric substations and substation sites of the Company including
all buildings, structures, towers, poles, lines, and all equipment, appliances,
and devices for transforming, converting and distributing electric energy, and
all the right, title and interest of the Company in and to the land on which the
same are situated, and all of the Company's lands, easements, rights-of-way,
rights, franchises, privileges, machinery, equipment, fixtures, appliances,
devices, appurtenances and supplies forming a part of said substation or any of
them, or used or enjoyed, or capable of being used or enjoyed, in conjunction or
connection therewith; and

          All warehouses, buildings, structures, works and sites and the
Company's lands on which the same are situated, and all easements,
rights-of-way, permits, franchises, consents, privileges, licenses, machinery,
equipment, furniture and fixtures, appurtenances and supplies forming a part of
said warehouses, buildings, structures, works and sites, or any of them, or used
or enjoyed or capable of being used or enjoyed in connection or conjunction
therewith; and

          All electric distribution systems of the Company, including towers,
poles, wires, insulators, appliances, devices, appurtenances and equipment, and
all the Company's other property, real, personal or mixed, forming a part of, or
used, occupied or enjoyed in connection with or in any way appertaining to said
distribution systems, or any of them, together with all of the Company's
rights-of-way, easements, permits, privileges, municipal or other franchises,
licenses, consents and rights for or relating to the construction, maintenance
or operation thereof through, over, under or upon any public streets or
highways, or public or private lands; and also all branches, extensions,
improvements and developments of or appertaining to or connected with said
electric distribution systems, or any of them, and all other electric
distribution systems of the Company and parts thereof wherever situated, and
whether now owned or hereafter acquired, as well as all rights-of-way,
easements, privileges, permits, municipal or other franchises, consents and
rights for or relating to the construction, maintenance or operation thereof, or
any part thereof, through, over, under or upon public or private lands, whether
now owned or hereafter acquired; and


                                       A-7
<PAGE>


          All electric transmission and/or distribution lines of the Company,
including the towers, poles, pole lines, wires, switch racks, insulators,
supports, guys, telephone and telegraph lines and other appliances and
equipment, and all other property of the Company, real, personal or mixed,
forming a part thereof or appertaining thereto, together with all of the
Company's rights-of-way, easements, permits, privileges, municipal or other
franchises, consents, licenses and rights, for or relating to the construction,
maintenance or operation thereof, through, over, under or upon any public
streets or highways or other lands, public or private; also all extension,
branches, taps, developments and improvements of or to any and all of the
above-described transmission and/or distribution lines, telephone and telegraph
lines or any of them, as well as all rights-of-way, easements, permits,
privileges, rights and municipal or other franchises, licenses and consents, for
or relating to the construction, maintenance or operation of said lines or any
of them, or any part thereof, through, over, under or upon any public streets or
highways or any public or private lands, whether now owned or hereafter
acquired;

          Excepting, however, any property of the character of "Excepted
Property" within the meaning of the Supplemental Indenture to which this
Schedule A is attached.

              SPECIFIC DESCRIPTION OF ANY ADDITIONAL REAL PROPERTY

          Specific descriptions of additional portions of the Mortgaged Property
which constitute real property, if any, are contained in Annex 1 to this
Schedule A.


                                       A-8
<PAGE>


                                     ANNEX 1
                                       TO
                                   SCHEDULE A

                                      None.


                                       A-9