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                                                                     EXHIBIT 4.2



                          FIRST SUPPLEMENTAL INDENTURE

                           Dated as of April   , 2000

                                     between

                                 METLIFE, INC.,

                                    AS ISSUER

                                       and

                              THE BANK OF NEW YORK,

                                   AS TRUSTEE
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                                TABLE OF CONTENTS

                                                                            Page
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<TABLE>
<CAPTION>
                                    ARTICLE I

                                   DEFINITIONS

<S>                                                                          <C>
Section 1.1     Definition of Terms............................................2

                                   ARTICLE II

                 GENERAL TERMS AND CONDITIONS OF THE DEBENTURES

Section 2.1     Designation, Principal Amount and Authorized Denomination......3
Section 2.2     Maturity.......................................................4
Section 2.3     Form and Payment...............................................4
Section 2.4     Global Debenture...............................................4
Section 2.5     Interest.......................................................6

                                   ARTICLE III

                                    EXPENSES

Section 3.1     Expenses.......................................................8
Section 3.2     Payment Upon Resignation or Removal............................9
Section 3.3     Indemnification................................................9

                                   ARTICLE IV

                                FORM OF DEBENTURE

Section 4.1     Form of Debenture.............................................12

                                    ARTICLE V

                          ORIGINAL ISSUE OF DEBENTURES

Section 5.1     Original Issue of Debentures..................................20
Section 5.2     Calculation of Original Issue Discount........................21
</TABLE>

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                                   ARTICLE VI

                                  MISCELLANEOUS

Section 6.1     Ratification of Base Indenture................................21
Section 6.2     Governing Law.................................................21
Section 6.3     Counterparts..................................................21

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           FIRST SUPPLEMENTAL INDENTURE, dated as of April __, 2000 (the "First
Supplemental Indenture"), between METLIFE, INC., a corporation duly organized
and existing under the laws of the State of Delaware, (the "Company"), and THE
BANK OF NEW YORK, a New York banking corporation, as trustee (the "Trustee").

           WHEREAS, the Company executed and delivered the indenture, dated as
of April __, 2000 (the "Base Indenture"), to the Trustee to provide for the
future issuance of the Company's debentures (the "Securities"), to be issued
from time to time in one or more series as might be determined by the Company
under the Base Indenture;

           WHEREAS, pursuant to the terms of the Base Indenture, the Company
desires to provide for the establishment of a new series of its Securities to be
known as its -% Debentures due 2005 (the "Debentures"), the form and substance
of such Debentures and the terms, provisions and conditions thereof to be set
forth as provided in the Base Indenture and this First Supplemental Indenture
(together, the "Indenture");

           WHEREAS, MetLife Capital Trust I, a Delaware statutory business trust
(the "Trust"), has offered to the public its -% Capital Securities (the "Capital
Securities"), representing undivided beneficial interests in the assets of the
Trust, and proposes to invest the proceeds from such offering, together with the
proceeds of the issuance and sale by the Trust to the Company of its -% Common
Securities (the "Common Securities" and together with the Capital Securities,
the "Trust Securities"), in the Debentures; and

           WHEREAS, the Company has requested that the Trustee execute and
deliver this First Supplemental Indenture and satisfy all requirements necessary
to make this First Supplemental Indenture a valid instrument in accordance with
its terms, and to make the Debentures, when executed by the Company and
authenticated and delivered by the Trustee, the valid obligations of the Company
and all acts and things necessary have been done and performed to make this
First Supplemental Indenture enforceable in accordance with its terms, and the
execution and delivery of this First Supplemental Indenture has been duly
authorized in all respects:

           NOW THEREFORE, in consideration of the purchase and acceptance of the
Debentures by the Holders thereof, and for the purpose of setting forth, as
provided in the Indenture, the form and substance of the Debentures and the
terms, provisions and conditions thereof, the Company covenants and agrees with
the Trustee as follows:
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                                    ARTICLE I

                                   DEFINITIONS

         Section 1.1 Definition of Terms. Unless the context otherwise requires:

           (a) a term defined in the Indenture has the same meaning when used in
      this First Supplemental Indenture;

           (b) a term defined anywhere in this First Supplemental Indenture has
      the same meaning throughout;

           (c)  the singular includes the plural and vice versa;

           (d) headings are for convenience of reference only and do not affect
      interpretation;

           (e) the following terms have the meanings given to them in the
      Declaration: Administrative Trustee; Capital Security Certificate;
      Delaware Trustee; Property Trustee; Purchase Contract Agreement;
      Remarketing Agent; Reset Agent; Reset Rate; and Underwriting Agreement.

           (f) the following terms have the meanings given to them in this
      Section 1.1(f):

           "Business Day" means any day that is not a Saturday, Sunday or day on
      which banking institutions and trust companies in The City of New York are
      authorized or required by law, regulation or executive order to close.

           "Collateral Agent" has the meaning set forth in the Purchase Contract
      Agreement.

           "Company Indemnified Person" has the meaning specified in the
      Declaration.

           "Declaration" means the Amended and Restated Declaration of Trust of
      MetLife Capital Trust I, a Delaware statutory business trust, dated as of
      April __, 2000.

           "Dissolution Event" means the dissolution of the Trust and the
      distribution of the Debentures held by the Property Trustee to the holders
      of the Trust Securities issued by the Trust pro rata in accordance with
      the Declaration.


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           "Failed Remarketing" has the meaning set forth in the Purchase
      Contract Agreement.

           "Global Debentures" shall have the meaning set forth in Section 2.4.

           "Interest Rate" shall have the meaning set forth in Section 2.5.

           "Non Book-Entry Capital Securities" shall have the meaning set forth
      in Section 2.4.

           "Normal Units" has the meaning set forth in the Purchase Contract
      Agreement.

           "Over-Allotment Option" shall mean the option granted to the
      underwriters pursuant to the Underwriting Agreement to purchase up to an
      additional - Normal Units.

           "Purchase Contract" shall have the meaning set forth in the Purchase
      Contract Agreement.

           "Purchase Contract Agreement" shall mean that certain agreement dated
      as of April __, 2000 between the Company and Bank One Trust Company, N.A.,
      as purchase contract agent.

           "Remarketing Date" has the meaning set forth in Purchase Contract
      Agreement.

           "Subsequent Remarketing Date" has the meaning set forth in the
      Purchase Contract Agreement.


                                   ARTICLE II

                 GENERAL TERMS AND CONDITIONS OF THE DEBENTURES

           Section 2.1 Designation, Principal Amount and Authorized
Denomination. There is hereby authorized a series of Securities designated the
-% Debentures due 2005 (the "Debentures"), limited in aggregate principal amount
to $1,000,000,000 (or up to $1,150,000,000, if the Over-Allotment Option is
exercised in full), which amount to be issued shall be as set forth in any
written order of the Company for the authentication and delivery of Debentures
pursuant to the Base Indenture. The denominations in which Debentures shall be
issuable is $50 and integral multiples thereof.



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           Section 2.2 Maturity. The Stated Maturity Date will be May 15, 2005.

           Section 2.3 Form and Payment. Except as provided in Section 2.4, the
Debentures shall be issued in fully registered certificated form without
interest coupons bearing identical terms. Principal, premium (if any) and
interest on the Debentures issued in certificated form will be payable, the
transfer of such Debentures will be registrable and such Debentures will be
exchangeable for Debentures bearing identical terms and provisions at the office
or agency of the Trustee; provided, however, that payment of interest may be
made at the option of the Company by check mailed to the Holder at such address
as shall appear in the Register or by wire transfer in immediately available
funds to the bank account number of the Holder specified in writing by the
Holder and entered in the Register by the Registrar. Notwithstanding the
foregoing, so long as the Holder of any Debentures is the Property Trustee, the
payment of the principal of and interest (including expenses and taxes of the
Trust set forth in Section 3.1 hereof, if any) on such Debentures held by the
Property Trustee will be made at such place and to such account as may be
designated in writing by the Property Trustee.

           Section 2.4 Global Debenture. (a) The Depository Trust Company shall
serve as the initial Depository for the Debentures.

           (b)  In connection with a Dissolution Event,

           (i) the Debentures in certificated form may be presented to the
      Trustee by the Property Trustee in exchange for a global Debenture in an
      aggregate principal amount equal to the aggregate principal amount of all
      outstanding Debentures (a "Global Debenture"), to be registered in the
      name of the Depository, or its nominee, and delivered by the Property
      Trustee to the Depository for crediting to the accounts of its
      participants pursuant to the instructions of the Administrative Trustees.
      The Company upon any such presentation shall execute a Global Debenture in
      such aggregate principal amount and deliver the same to the Trustee for
      authentication and delivery in accordance with the Indenture. The Trustee,
      upon receipt of such Global Debenture, together with an Officers'
      Certificate requesting authentication, will authenticate such Global
      Debenture. Payments on the Debentures issued as a Global Debenture will be
      made to the Depository; and

           (ii) if any Capital Securities are held in non book-entry
      certificated form, the Debentures in certificated form may be presented to
      the Trustee by the Property Trustee and any Capital Security Certificate
      which represents Capital Securities other than Capital Securities held by
      the Depository or its nominee ("Non Book-Entry Capital Securities") will
      be deemed to represent beneficial interests in the Debentures presented to
      the Trustee by the Property Trustee having an aggregate principal



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      amount equal to the aggregate liquidation amount of the Non Book-Entry
      Capital Securities until such Capital Security Certificates are presented
      to the Property Trustee for transfer or reissuance at which time such
      Capital Security Certificates will be cancelled and a Debenture,
      registered in the name of the Holder of the Capital Security Certificate
      or the transferee of the Holder of such Capital Security Certificate, as
      the case may be, with an aggregate principal amount equal to the aggregate
      liquidation amount of the Capital Security Certificate cancelled, will be
      executed by the Company and delivered to the Trustee for authentication
      and delivery in accordance with the Indenture to such Holder. The Trustee,
      upon receipt of such Debenture together with an Officers' Certificate
      requesting authentication, shall authenticate such Debenture. On issue of
      such Debentures, Debentures with an equivalent aggregate principal amount
      that were presented by the Property Trustee to the Trustee will be deemed
      to have been cancelled.

           (c) Unless and until it is exchanged for the Debentures in registered
form, a Global Debenture may be transferred, in whole but not in part, only to
another nominee of the Depository, or to a successor Depository selected or
approved by the Company or to a nominee of such successor Depository.

           (d) If (a) at any time the Depository for Global Debentures notifies
the Company that it is unwilling or unable to continue as Depository for such
Global Debentures or if at any time the Depository for such Global Debentures
shall no longer be a clearing agency registered or in good standing under the
Exchange Act or other applicable statute or regulation, and a successor
Depository for such Global Debentures is not appointed by the Company within 90
days after the Company receives such notice or becomes aware of such condition,
as the case may be, or (b) the Company determines in its sole discretion that
the Debentures shall no longer be represented by one or more Global Debentures
and delivers to the Trustee an Officer's Certificate evidencing such
determination, then the Company will execute and the Trustee, upon receipt of an
Officer's Certificate evidencing such determination by the Company, will
authenticate and deliver Debentures of like tenor in definitive registered form,
in authorized denominations, and in aggregate principal amount equal to the
principal amount of the Global Debentures in exchange for such Global
Debentures. Upon the exchange of Global Debentures for such Debentures in
definitive registered form without coupons, in authorized denominations, the
Global Debentures shall be canceled by the Trustee. Such Debentures in
definitive registered form issued in exchange for Global Debentures pursuant to
this Section shall be registered in such names and in such authorized
denominations as the Depository, pursuant to instructions from its direct or
indirect participants or otherwise, shall instruct the Trustee. The Trustee
shall deliver such Debentures to the Persons in whose names such Debentures are
so registered.


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           Section 2.5 Interest. (a) Each Debenture will bear interest initially
at the rate of -% per annum (the "Interest Rate") from the original date of
issuance through and including February 15, 2003, and thereafter at the Reset
Rate in accordance with Section 2.5(b) and notified to the Trustee by the
Company (the "Reset Rate"), until the principal thereof becomes due and payable,
and on any overdue principal, premium (if any) and (to the extent that payment
of such interest is enforceable under applicable law) on any overdue installment
of interest at the Interest Rate through and including February 15, 2003 and at
the Reset Rate thereafter, compounded quarterly, payable (subject to the
provisions of Section 2.5(c) and Article III herein) quarterly in arrears on
February 15, May 15, August 15 and November 15 of each year (each, an "Interest
Payment Date") commencing on August 15, 2000, to the Person in whose name such
Debenture or any predecessor Debenture is registered, at the close of business
on the regular record date for such interest installment, which, in respect of
(i) Debentures of which the Property Trustee is the Holder and the Capital
Securities are in book-entry only form or (ii) a Global Debenture, shall be the
close of business on the Business Day next preceding that Interest Payment Date.
Notwithstanding the foregoing sentence, if (i) the Debentures are held by the
Property Trustee and the Capital Securities are no longer in book-entry only
form or (ii) the Debentures are not represented by a Global Debenture, the
Company may select a regular record date for such interest installment which
shall be more than one Business Day but less than 60 Business Days prior to an
Interest Payment Date.

           (b) The interest rate on the Debentures will be reset on the
Remarketing Date or any Subsequent Remarketing Date, as the case may be, to the
Reset Rate determined by the Reset Agent in accordance with Annex I to the
Declaration (which Reset Rate will become effective from and after February 16,
2003); provided, however, if there has been a Failed Remarketing, the Reset Rate
will be equal to the Interest Rate until the Capital Securities are successfully
remarketed pursuant to the Purchase Contract Agreement.

           (c) So long as no Event of Default has occurred and is continuing,
the Company shall have the right at any time, and from time to time, during the
term of the Debentures, to defer payments of interest by extending the interest
payment period of such Debentures for a period not extending, in the aggregate,
beyond the Stated Maturity Date (the "Deferral Period"), during which Deferral
Period no interest shall be due and payable. To the extent permitted by
applicable law, interest, the payment of which has been deferred because of the
extension of the interest payment period pursuant to this Section 2.5(c), will
bear interest thereon at the Interest Rate through and including February 15,
2003, and, subject to paragraph (b) above, at the Reset Rate thereafter,
compounded quarterly for each quarter of the Deferral Period ("Compounded
Interest"). At the end of the Deferral Period, the Company shall pay all
interest accrued and unpaid on the Debentures and Compounded Interest (together,
"Deferred Interest") that shall be payable to the Holders of the Debentures in
whose names the Debentures are registered in the Register


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on the first record date after the end of the Deferral Period. Prior to the
termination of any Deferral Period, the Company may further extend such period,
provided that such period together with all such previous and further extensions
thereof shall not extend beyond the Stated Maturity Date. Upon the termination
of any Deferral Period and the payment of all Deferred Interest then due, the
Company may commence a new Deferral Period, subject to the foregoing
requirements. No interest shall be due and payable during a Deferral Period,
except at the end thereof, but the Company, at its option, may prepay on any
Interest Payment Date all or any portion of the interest accrued during the then
elapsed portion of a Deferral Period. The Company shall give the Trustee written
notice of the Company's election to begin a Deferral Period for the Debentures
and any shortening or extension thereof at least five Business Days prior to the
earlier of (i) the date the interest on such Debentures or distributions on the
Capital Securities are payable or (ii) the date the trustees of the Trust are
required to give notice to the New York Stock Exchange or other applicable
self-regulatory organization or to holders of the Capital Securities of the
record date or the date such distributions are payable, but in any event not
less than five Business Days prior to such record date. The Company shall give
or cause the Trustee to give notice at the expense of the Company (a form of
which shall be provided by the Company to the Trustee) of the Company's election
to begin a Deferral Period to the Holders by first class mail, postage prepaid.

           (d) The amount of interest payable for any period will be computed on
the basis of a 360-day year consisting of twelve 30-day months. Except as
provided in the following sentence, the amount of interest payable for any
period shorter than a full quarterly period for which interest is computed will
be computed on the basis of the actual number of days elapsed in such a 90-day
period. In the event that any date on which interest is payable on the
Debentures is not a Business Day, then payment of 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 such date.

           (e) The Debentures are not entitled to any sinking fund payments.


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                                   ARTICLE III

                                    EXPENSES

           Section 3.1 Expenses. In connection with the offering, sale and
issuance of the Debentures to the Property Trustee and in connection with the
sale of the Securities by the Trust, the Company, in its capacity as borrower
with respect to the Debentures, shall:

           (a) pay all costs and expenses relating to the offering, sale and
      issuance of the Debentures, including commissions to the underwriters
      payable pursuant to the Underwriting Agreement and compensation of the
      Trustee under this Indenture in accordance with the provisions of this
      Indenture;

           (b) be responsible for and shall pay all debts and obligations (other
      than with respect to the Securities and other than with respect to taxes)
      and all costs and expenses of the Trust (including, but not limited to,
      costs and expenses relating to the organization, maintenance and
      dissolution of the Trust), the offering, sale and issuance of the
      Securities (including commissions to the underwriters in connection
      therewith), the fees and expenses (including reasonable counsel fees and
      expenses) of the Property Trustee, the Delaware Trustee and the
      Administrative Trustees (including any amounts payable under Section 3.3
      hereof and Article X of the Declaration), the costs and expenses relating
      to the operation of the Trust, including, without limitation, costs and
      expenses of accountants, attorneys, statistical or bookkeeping services,
      expenses for printing and engraving and computing or accounting
      equipment, paying agent(s), registrar(s), transfer agent(s), duplicating,
      travel and telephone and other telecommunications expenses and costs and
      expenses incurred in connection with the acquisition, financing, and
      disposition of Trust assets and the enforcement by the Property Trustee
      of the rights of the Holders of the Securities;

           (c) be primarily liable for any indemnification obligations arising
      under Section 3.3 with respect to this Indenture; and

           (d) pay any and all taxes (other than United States withholding taxes
      attributable to the Trust or its assets) and all liabilities, costs and
      expenses with respect to such taxes of the Trust.

           The Company's obligations under this Section 3.1 shall be for the
benefit of, and shall be enforceable by, any person to whom such debts,
obligations, costs, expenses and taxes are owed (a "Creditor") whether or not
such Creditor has received notice hereof. Any such Creditor may enforce the
Company's obligations under this Section 3.1 directly against the Company and
the Company irrevocably waives any right or remedy to require


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that any such Creditor take any action against the Trust or any other Person
before proceeding against the Company. The Company agrees to execute such
additional agreements as may be necessary or desirable in order to give full
effect to the provisions of this Section 3.1.

           Section 3.2 Payment Upon Resignation or Removal. Upon termination of
this First Supplemental Indenture or the Base Indenture or the removal or
resignation of the Trustee, the Company shall pay to the Trustee all amounts
then owing to the Trustee under Section 7.7 of the Base Indenture. Upon
termination of the Declaration or the removal or resignation of the Delaware
Trustee or the Property Trustee, as the case may be, pursuant to Section 5.6 of
the Declaration, the Company shall pay to the Delaware Trustee or the Property
Trustee, as the case may be, all amounts accrued to the date of such
termination, removal or resignation.

           Section 3.3 Indemnification. (a) (i) The Company shall indemnify, to
the fullest extent permitted by law, any Company Indemnified Person who was or
is a party or is threatened to be made a party to any threatened, pending or
completed action, suit or proceeding, whether civil, criminal, administrative or
investigative (other than an action by or in the right of the Trust) by reason
of the fact that he is or was a Company Indemnified Person against expenses
(including reasonable attorneys' fees), judgments, fines and amounts paid in
settlement actually and reasonably incurred by him in connection with such
action, suit or proceeding if he acted in good faith and in a manner he
reasonably believed to be in or not opposed to the best interests of the Trust,
and, with respect to any criminal action or proceeding, had no reasonable cause
to believe his conduct was unlawful. The termination of any action, suit or
proceeding by judgment, order, settlement, conviction, or upon a plea of nolo
contendere or its equivalent, shall not, of itself, create a presumption that
the Company Indemnified Person did not act in good faith and in a manner which
he reasonably believed to be in or not opposed to the best interests of the
Trust, and, with respect to any criminal action or proceeding, had reasonable
cause to believe that his conduct was unlawful.

           (ii) The Company shall indemnify, to the fullest extent permitted by
law, any Company Indemnified Person who was or is a party or is threatened to be
made a party to any threatened, pending or completed action or suit by or in the
right of the Trust to procure a judgment in its favor by reason of the fact that
he is or was a Company Indemnified Person against expenses (including reasonable
attorneys' fees) actually and reasonably incurred by him in connection with the
defense or settlement of such action or suit if he acted in good faith and in a
manner he reasonably believed to be in or not opposed to the best interests of
the Trust and except that no such indemnification shall be made in respect of
any claim, issue or matter as to which such Company Indemnified Person shall
have been adjudged to be liable to the Trust unless and only to the extent that


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the Court of Chancery of Delaware or the court in which such action or suit was
brought shall determine upon application that, despite the adjudication of
liability but in view of all the circumstances of the case, such person is
fairly and reasonably entitled to indemnity for such expenses which such Court
of Chancery or such other court shall deem proper.

           (iii) Any indemnification under paragraphs (i) and (ii) of this
Section 3.3(a) (unless ordered by a court) shall be made by the Company only as
authorized in the specific case upon a determination that indemnification of the
Company Indemnified Person is proper in the circumstances because he has met the
applicable standard of conduct set forth in paragraphs (i) and (ii). Such
determination shall be made (1) by the Administrative Trustees by a majority
vote of a quorum consisting of such Administrative Trustees who were not parties
to such action, suit or proceeding, (2) if such a quorum is not obtainable, or,
even if obtainable, if a quorum of disinterested Administrative Trustees so
directs, by independent legal counsel in a written opinion, or (3) by the Common
Security Holder of the Trust.

           (iv) Expenses (including reasonable attorneys' fees) incurred by a
Company Indemnified Person in defending a civil, criminal, administrative or
investigative action, suit or proceeding referred to in paragraphs (i) and (ii)
of this Section 3.3(a) shall be paid by the Debenture Issuer in advance of the
final disposition of such action, suit or proceeding upon receipt of an
undertaking by or on behalf of such Company Indemnified Person to repay such
amount if it shall ultimately be determined that such person is not entitled to
be indemnified by the Debenture Issuer as authorized in this Section 3.3(a).
Notwithstanding the foregoing, no advance shall be made by the Debenture Issuer
if a determination is reasonably and promptly made (i) by the Administrative
Trustees by a majority vote of a quorum of disinterested Administrative
Trustees, (ii) if such a quorum is not obtainable, or, even if obtainable, if a
quorum of disinterested Administrative Trustees so directs, by independent legal
counsel in a written opinion or (iii) the Common Security Holder of the Trust,
that, based upon the facts known to the Administrative Trustees, independent
legal counsel or Common Security Holder at the time such determination is made,
such person acted in bad faith or in a manner that such person did not believe
to be in or not opposed to the best interests of the Trust, or, with respect to
any criminal proceeding, that such Company Indemnified Person believed or had
reasonable cause to believe his conduct was unlawful. In no event shall any
advance be made in instances where the Administrative Trustees, independent
legal counsel or Common Security Holder reasonably determine that such person
deliberately breached such person's duty to the Trust or its Common or Capital
Security Holders.

           (v) The indemnification and advancement of expenses provided by, or
granted pursuant to, the other paragraphs of this Section 3.3(a) shall not be
deemed exclusive of any other rights to which those seeking indemnification and
advancement of expenses may


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<PAGE>   14
be entitled under any agreement, vote of shareholders or disinterested directors
of the Company or Capital Security Holders of the Trust or otherwise, both as to
action in his official capacity and as to action in another capacity while
holding such office. All rights to indemnification under this Section 3.3(a)
shall be deemed to be provided by a contract between the Company and each
Company Indemnified Person who serves in such capacity at any time while this
Section 3.3(a) is in effect. Any repeal or modification of this Section 3.3(a)
shall not affect any rights or obligations then existing.

           (vi) The Company or the Trust may purchase and maintain insurance on
behalf of any person who is or was a Company Indemnified Person against any
liability asserted against him and incurred by him in any such capacity, or
arising out of his status as such, whether or not the Company would have the
power to indemnify him against such liability under the provisions of this
Section 3.3(a).

           (vii) For purposes of this Section 3.3(a), references to "the Trust"
shall include, in addition to the resulting or surviving entity, any constituent
entity (including any constituent of a constituent) absorbed in a consolidation
or merger, so that any person who is or was a director, trustee, officer or
employee of such constituent entity, or is or was serving at the request of such
constituent entity as a director, trustee, officer, employee or agent of another
entity, shall stand in the same position under the provisions of this Section
3.3(a) with respect to the resulting or surviving entity as such person would
have with respect to such constituent entity if its separate existence had
continued.

           (viii) The indemnification and advancement of expenses provided by,
or granted pursuant to, this Section 3.3(a) shall, unless otherwise provided
when authorized or ratified, continue as to a person who has ceased to be a
Company Indemnified Person and shall inure to the benefit of the successors,
heirs, executors and administrators of such a person.

           (b) To the fullest extent permitted by law, the Company agrees to
indemnify the (i) Property Trustee including in its individual capacity, (ii)
the Delaware Trustee (including in its individual capacity), (iii) any Affiliate
of the Property Trustee or the Delaware Trustee, and (iv) any officers,
directors, shareholders, members, partners, employees, representatives,
custodians, nominees or agents of the Property Trustee or the Delaware Trustee
(each of the Persons in (i) through (iv) being referred to as a "Fiduciary
Indemnified Person") for, and to hold each Fiduciary Indemnified Person harmless
against, any loss, liability or expense to the extent incurred without gross
negligence and, in the case of the Property Trustee, pursuant to Section 3.9,
negligence or bad faith on its part, arising out of or in connection with the
acceptance or administration of the trust or trusts hereunder, including the
costs and expenses (including reasonable legal fees and expenses) of defending
itself against or investigating any claim (whether asserted by the issuer, any


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<PAGE>   15
Holder or any other person) or liability in connection with the exercise or
performance of any of its powers or duties hereunder. The provisions of this
Section 3.3(b) shall survive the satisfaction and discharge of this Declaration
and any resignation or removal of the Property Trustee or the Delaware Trustee,
as the case may be.


                                   ARTICLE IV

                                FORM OF DEBENTURE

           Section 4.1 Form of Debenture. The Debentures and the Trustee's
Certificate of Authentication to be endorsed thereon are to be substantially in
the following forms:

           [IF THE DEBENTURE IS TO BE A GLOBAL DEBENTURE, INSERT - This
      Debenture is a Global Debenture within the meaning of the Indenture
      hereinafter referred to and is registered in the name of the Depository or
      a nominee of the Depository. This Debenture is exchangeable for Debentures
      registered in the name of a person other than the Depository or its
      nominee only in the limited circumstances described in the Indenture, and
      no transfer of this Debenture (other than a transfer of this Debenture as
      a whole by the Depository to a nominee of the Depository or by a nominee
      of the Depository to the Depository or another nominee of the Depository)
      may be registered except in limited circumstances.

           Unless this Debenture is presented by an authorized representative of
The Depository Trust Company (55 Water Street, New York, New York) to the issuer
or its agent for registration of transfer, exchange or payment, and any
Debenture issued is registered in the name of Cede & Co. or such other name as
requested by an authorized representative of The Depository Trust Company and
any payment hereon is made to Cede & Co., ANY TRANSFER, PLEDGE OR OTHER USE
HEREOF FOR VALUE OR OTHERWISE BY A PERSON IS WRONGFUL since the registered owner
hereof, Cede & Co., has an interest herein.]


                                       12
<PAGE>   16
No. ___________________

CUSIP No. ______________                                  $_____________________

                                  METLIFE, INC.
                              -% DEBENTURE DUE 2005

           METLIFE, INC., a Delaware corporation (the "Company", which term
includes any successor corporation under the Indenture hereinafter referred to),
for value received, hereby promises to pay to __________________________, the
principal sum of ($______________) on May 15, 2005 (such date is hereinafter
referred to as the "Stated Maturity Date"), and to pay interest on said
principal sum from ____________ __, 2003, or from the most recent interest
payment date (each such date, an "Interest Payment Date") to which interest has
been paid or duly provided for, quarterly in arrears (subject to deferral as set
forth herein) on February 15, May 15, August 15, and November 15 of each year,
commencing on August 15, 2000, initially at the rate of -% per annum through and
including February 15, 2003, and at the Reset Rate thereafter, until the
principal hereof shall have become due and payable, and on any overdue principal
and premium, if any, 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 -% through and including February 15, 2003, and at the
Reset Rate thereafter, until the principal hereof shall have become due and
payable, compounded quarterly. The interest rate will be reset on the third
Business Day preceding February 15, 2003 to the Reset Rate (as determined by the
Reset Agent); provided, however, if there has been a Failed Remarketing, the
Reset Rate will be equal to the Interest Rate until the Capital Securities are
successfully remarketed pursuant to the Purchase Contract Agreement. The amount
of interest payable on any Interest Payment Date shall be computed on the basis
of a 360-day year consisting of twelve 30-day months. In the event that any date
on which interest is payable on this Debenture is not a Business Day, then
payment of interest payable on such date will be made on the next succeeding day
that 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 such date. 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 Debenture is registered at the close of business on
the regular record date for such interest installment, which in the case of a
Global Debenture shall be the close of business on the Business Day next
preceding such Interest Payment Date; provided, however, if pursuant to the
terms of the Indenture the Debentures are no longer represented by a Global
Debenture, the Company may select such regular record date for such interest
installment which shall be more than one Business Day but less than


                                       13
<PAGE>   17
60 Business Days prior to an Interest Payment Date. Any such interest
installment not punctually paid or duly provided for shall forthwith cease to be
payable to the registered Holders on such regular record date and may be paid to
the Person in whose name this Debenture is registered at the close of business
on a special record date to be fixed by the Trustee for the payment of such
defaulted interest, notice whereof shall be given to the registered Holders of
this series of Debentures not less than 10 days prior to such special record
date, or may be paid at any time in any other lawful manner not inconsistent
with the requirements of any securities exchange on which the Debentures may be
listed, and upon such notice as may be required by such exchange all as more
fully provided in the Indenture. The principal of (and premium, if any) and the
interest on this Debenture shall be payable at the office or agency of the
Trustee maintained for that purpose in any coin or currency of the United States
of America that at the time of payment is legal tender for payment of public and
private debts; provided, however, that payment of interest may be made at the
option of the Company by check mailed to the registered Holder at such address
as shall appear in the Register or by wire transfer to an account appropriately
designated by the Holder entitled thereto. Notwithstanding the foregoing, so
long as the Holder of this Debenture is the Property Trustee or the Collateral
Agent, the payment of the principal of (and premium, if any) and interest on
this Debenture will be made at such place and to such account as may be
designated in writing by the Property Trustee.

           So long as no Event of Default has occurred and is continuing, the
Company shall have the right at any time, and from time to time, during the term
of this Debenture, to defer payments of interest by extending the interest
payment period of such Debenture for a period not extending, in the aggregate,
beyond the Stated Maturity Date (the "Deferral Period"), during which Deferral
Period no interest shall be due and payable. To the extent permitted by
applicable law, interest, the payment of which has been deferred because of the
extension of the interest payment period pursuant to the provisions of this
Debenture, will bear interest thereon at the rate of -% through and including
February 15, 2003, and at the Reset Rate thereafter, compounded quarterly for
each quarter of the Deferral Period ("Compounded Interest"). At the end of the
Deferral Period, the Company shall pay all interest accrued and unpaid on this
Debenture and Compounded Interest (together, "Deferred Interest") that shall be
payable to the Holders of this Debenture in whose names this Debenture are
registered in the Register on the first record date after the end of the
Deferral Period. Prior to the termination of any Deferral Period, the Company
may further extend such period, provided that such period together with all such
previous and further extensions thereof shall not extend beyond the Stated
Maturity Date. Upon the termination of any Deferral Period and the payment of
all Deferred Interest then due, the Company may commence a new Deferral Period,
subject to the foregoing requirements. No interest shall be due and payable
during an Deferral Period, except at the end thereof, but the Company, at its
option, may prepay on any Interest Payment Date all or any portion of the
interest accrued during the then elapsed


                                       14
<PAGE>   18
portion of a Deferral Period. The Company shall give the Trustee written notice
of the Company's election to begin a Deferral Period for this Debenture and any
shortening or extension thereof at least five Business Days prior to the earlier
of (i) the date the interest on such Debenture or distributions on the Capital
Securities are payable or (ii) the date the trustees of the Trust are required
to give notice to the New York Stock Exchange or other applicable
self-regulatory organization or to holders of the Capital Securities of the
record date or the date such Distributions are payable, but in any event not
less than five Business Days prior to such record date. The Company shall give
or cause the Trustee to give notice at the Company's expense (a form of which
shall be provided by the Company to the Trustee) of the Company's election to
begin a Deferral Period to the Holders by first class mail, postage prepaid.

           This Debenture shall not be entitled to any benefit under the
Indenture hereinafter referred to, be valid or become obligatory for any purpose
until the Certificate of Authentication hereon shall have been signed by or on
behalf of the Trustee.

           The provisions of this Debenture are continued on the reverse side
hereof and such continued provisions shall for all purposes have the same effect
as though fully set forth at this place.


                                       15
<PAGE>   19
           IN WITNESS WHEREOF, the Company has caused this instrument to be
executed.

Dated:

                                  METLIFE, INC.


                                                By: _________________________
                                                Name:
                                                Title:


                                                By: _________________________
                                                Name:
                                                Title:

Attest


By: ___________________________
Name:
Title:


                          CERTIFICATE OF AUTHENTICATION

           This is one of the Debentures of the series designated therein
referred to in the within-mentioned Indenture.

Dated:

                                                THE BANK OF NEW YORK,
                                                as Trustee


                                                By: _________________________
                                                      Authorized Signatory


                                       16
<PAGE>   20
                         (FORM OF REVERSE OF DEBENTURE)

           This Debenture is one of a duly authorized series of the debentures
of the Company (herein sometimes referred to as the "Securities"), specified in
the Indenture hereinafter referred to, all issued or to be issued in one or more
series under and pursuant to an Indenture dated as of April __, 2000 (the "Base
Indenture"), duly executed and delivered between the Company and The Bank of New
York, as Trustee (the "Trustee") (such Base Indenture as supplemented by the
First Supplemental Indenture, dated April __, 2000, the "Indenture"), to which
Indenture and all indentures supplemental thereto reference is hereby made for a
description of the rights, limitations of rights, obligations, duties and
immunities thereunder of the Trustee, the Company and the Holders of the
Securities. By the terms of the Indenture, the Securities are issuable in series
that may vary as to amount, date of maturity, rate of interest and in other
respects as provided in the Indenture. This series of Securities is limited in
aggregate principal amount as specified in said First Supplemental Indenture.

           The Debentures are not entitled to the benefit of any sinking fund.

           In case an Event of Default, as defined in the Indenture, shall have
occurred and be continuing, the principal of all of the Debentures may be
declared, and upon such declaration shall become, due and payable, in the
manner, with the effect and subject to the conditions provided in the Indenture.

           The Indenture contains provisions permitting the Company and the
Trustee, with the consent of the Holders of not less than a majority in
aggregate principal amount of the Securities of each series affected at the time
outstanding, as defined in the Indenture, to execute supplemental indentures for
the purpose of, among other things, adding any provisions to or changing in any
manner or eliminating any of the provisions of the Indenture or of any
supplemental indenture or of modifying in any manner the rights of the Holders
of the Securities; provided, however, that, among other things, no such
supplemental indenture shall (i) reduce the principal amount thereof, or reduce
the rate or extend the time of payment of interest thereon, or reduce any
premium payable upon the redemption thereof, without the consent of the Holder
of each Security so affected, or (ii) reduce the aforesaid percentage of
Securities, the Holders of which are required to consent to any such
supplemental indenture, without the consent of the Holders of each Security then
outstanding and affected thereby. The Indenture also contains provisions
permitting the Holders of a majority in aggregate principal amount of the
Securities of any series at the time outstanding affected thereby, on behalf of
all of the Holders of the Securities of such series, to waive a Default or Event
of Default with respect to such series, and its consequences, except a Default
or Event of Default in the payment of the principal of or premium, if any, or
interest on any of the Securities of such series or a


                                       17
<PAGE>   21
Default in respect of a provision that under Section 6.4 of the Base Indenture
cannot be amended without the consent of each holder affected thereby. Any such
consent or waiver by the registered Holder of this Debenture (unless revoked as
provided in the Indenture) shall be conclusive and binding upon such Holder and
upon all future Holders and owners of this Debenture and of any Debenture issued
in exchange for or in place hereof (whether by registration of transfer or
otherwise), irrespective of whether or not any notation of such consent or
waiver is made upon this Debenture.

           No reference herein to the Indenture and no provision of this
Debenture 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 Debenture at the time and place and at the
rate and in the money herein prescribed.

           As provided in the Indenture and subject to certain limitations
therein set forth, this Debenture is transferable by the registered Holder
hereof on the Register of the Company, upon surrender of this Debenture for
registration of transfer at the office or agency of the Trustee in the City of
New York and State of New York accompanied by a written instrument or
instruments of transfer in form satisfactory to the Company or the Trustee duly
executed by the registered Holder hereof or his attorney duly authorized in
writing, and thereupon one or more new Debentures of authorized denominations
and for the same aggregate principal amount and series will be issued to the
designated transferee or transferees. No service charge will be made for any
such transfer, but the Company may require payment of a sum sufficient to cover
any tax, assessment or other governmental charge payable in relation thereto.

           Prior to due presentment for registration of transfer of this
Debenture, the Company, the Trustee, any paying agent and the Registrar may deem
and treat the registered holder hereof as the absolute owner hereof (whether or
not this Debenture shall be overdue and notwithstanding any notice of ownership
or writing hereon made by anyone other than the Registrar) for the purpose of
receiving payment of or on account of the principal hereof and premium, if any,
and interest due hereon and for all other purposes, and neither the Company nor
the Trustee nor any paying agent nor any Registrar shall be affected by any
notice to the contrary.

           No recourse shall be had for the payment of the principal of or the
interest on this Debenture, or for any claim based hereon, or otherwise in
respect hereof, or based on or in respect of the Indenture, against any
incorporator, shareholder, officer or director, past, present or future, as
such, of the Company or of 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 otherwise, all such liability being, by the acceptance
hereof and as part of the consideration for the issuance hereof, expressly
waived and released.


                                       18
<PAGE>   22
           The Indenture imposes certain limitations on the ability of the
Company to, among other things, merge or consolidate with any other Person or
sell, assign, transfer, lease or convey all or substantially all of its
properties and assets. All such covenants and limitations are subject to a
number of important qualifications and exceptions. The Company must report
periodically to the Trustee on compliance with the covenants in the Indenture.

           The Debentures of this series are issuable only in registered form
without coupons, in denominations of $50 and any integral multiple thereof. As
provided in the Indenture and subject to certain limitations therein set forth,
Debentures of this series so issued are exchangeable for a like aggregate
principal amount of Debentures of this series of a different authorized
denomination, as requested by the Holder surrendering the same.

           All terms used in this Debenture that are defined in the Indenture
shall have the meanings assigned to them in the Indenture.

           This Debenture shall be governed by and construed in accordance with
the laws of the State of New York, without regard to its principles of conflicts
of laws.


                                       19
<PAGE>   23
                                   ASSIGNMENT

FOR VALUE RECEIVED, the undersigned assigns and transfers this Debenture to:

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


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


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

        (Insert assignee's social security or tax identification number)


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


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


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

                    (Insert address and zip code of assignee)

agent to transfer this Debenture on the books of the Trust. The agent may
substitute another to act for him or her.

Dated:                                          Signature:

                                                Signature Guarantee:

     (Sign exactly as your name appears on the other side of this Debenture)

           Signatures must be guaranteed by an "eligible guarantor institution"
meeting the requirements of the Registrar, which requirements include membership
or participation in the Security Transfer Agent Medallion Program ("STAMP") or
such other "signature guarantee program" as may be determined by the Debt
Security Registrar in addition to, or in substitution for, STAMP, all in
accordance with the Securities Exchange Act of 1934, as amended.


                                    ARTICLE V

                          ORIGINAL ISSUE OF DEBENTURES

           Section 5.1 Original Issue of Debentures. Debentures in the aggregate
principal amount of $1,000,000,000 (or up to $1,150,000,000, if the
Over-Allotment Option is exercised) may, upon execution of this First
Supplemental Indenture, be executed by the Company and delivered to the Trustee
for authentication, and the Trustee shall thereupon authenticate and deliver
said Debentures in accordance with a Company Order. The Issue Date of the
Debentures shall be April __, 2000.


                                       20
<PAGE>   24
                                   ARTICLE VI

                                  MISCELLANEOUS

           Section 6.1 Ratification of Base Indenture. The Base Indenture as
supplemented by this First Supplemental Indenture, is in all respects ratified
and confirmed, and this First Supplemental Indenture shall be deemed part of the
Base Indenture in the manner and to the extent herein and therein provided.

           Section 6.2  Governing Law.  THIS FIRST SUPPLEMENTAL INDENTURE
AND EACH DEBENTURE SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK, WITHOUT
REGARD TO ITS PRINCIPLES OF CONFLICTS OF LAWS.

           Section 6.3 Counterparts. This First Supplemental Indenture may be
executed in any number of counterparts each of which shall be an original; but
such counterparts shall together constitute but one and the same instrument.


                                       21
<PAGE>   25
           IN WITNESS WHEREOF, the parties hereto have caused this First
Supplemental Indenture to be duly executed by their respective officers
thereunto duly authorized, on the date or dates indicated in the acknowledgments
and as of the day and year first above written.

                                             METLIFE, INC.,
                                             as Issuer


                                             By:
                                             Name:
                                             Title:


                                             THE BANK OF NEW YORK,
                                             as Trustee

                                             By:
                                             Name:
                                             Title:


                                       22