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                                                                    Exhibit 4(g)

                                     Form of
                      Common Securities Guarantee Agreement

                              BGE Capital Trust II


                                   Dated as of

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                                TABLE OF CONTENTS

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                                    ARTICLE I

                                   DEFINITIONS

SECTION 1.01.   Definitions..................................................2
SECTION 1.02.   Interpretation...............................................3

                                   ARTICLE II

                                    GUARANTEE

SECTION 2.01.   Guarantee....................................................4
SECTION 2.02.   Waiver of Notice and Demand..................................4
SECTION 2.03.   Obligations Not Affected.....................................4
SECTION 2.04.   Rights of Holders............................................5
SECTION 2.05.   Guarantee of Payment.........................................6
SECTION 2.06.   Subrogation..................................................6
SECTION 2.07.   Independent Obligations......................................6

                                   ARTICLE III

                                  SUBORDINATION

SECTION 3.01.   Ranking......................................................6
SECTION 3.02.   PARI PASSU Guarantees........................................7

                                   ARTICLE IV

                                   TERMINATION

SECTION 4.01.   Termination..................................................7

                                    ARTICLE V

                                  MISCELLANEOUS

SECTION 5.01.   Successors and Assigns.......................................8
SECTION 5.02.   Amendments...................................................8
SECTION 5.03.   Notices......................................................8
SECTION 5.04.   Benefit......................................................9
SECTION 5.05.   Governing Law................................................9
SECTION 5.06.   Counterparts.................................................9
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                               GUARANTEE AGREEMENT

     This GUARANTEE AGREEMENT (the "Common Securities Guarantee"), dated as
of________, is executed and delivered by Baltimore Gas and Electric Company, a
Maryland corporation (the "Guarantor"), for the benefit of the Holders (as
defined herein) from time to time of the Common Securities (as defined herein)
of BGE Capital Trust II, a Delaware statutory trust (the "Issuer").

     WHEREAS, pursuant to an Amended and Restated Declaration of Trust (the
"Declaration"), dated as of ______________ among the Trustees named therein, the
Guarantor, as Depositor, and the Holders from time to time of common undivided
beneficial interests in the assets of the Issuer, the Issuer is issuing on the
date hereof common securities having an aggregate liquidation amount of $25.00
per security) for an aggregate stated liquidation amount of $7,731,950,
designated the ___% Common Securities (the "Common Securities") representing
undivided beneficial interests in the assets of the Issuer and having the terms
set forth in the Declaration;

     WHEREAS, the Common Securities will be issued by the Issuer and the
proceeds thereof, together with the proceeds from the sale by the Issuer of its
Preferred Securities (as defined herein), will be used to purchase the
Debentures (as defined in the Declaration) of the Guarantor which will be
deposited with The Bank of New York, as Property Trustee under the Declaration,
as Trust Property (as defined in the Declaration);

     WHEREAS, as incentive for the Holders to purchase Common Securities, the
Guarantor desires irrevocably and unconditionally to agree, to the extent set
forth herein, to pay to the Holders of the Common Securities the Guarantee
Payments (as defined herein) and to make certain other payments on the terms and
conditions set forth herein; and

     WHEREAS, the Guarantor is also executing and delivering a guarantee
agreement (the "Preferred Securities Guarantee") in substantially identical
terms to this Common Securities Guarantee for the benefit of the holders of the
Preferred Securities, except that if an Event of Default (as defined in the
Indenture) has occurred and is continuing, the rights of the Holders of the
Common Securities to receive Guarantee Payments under this Common Securities
Guarantee

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are subordinated to the rights of Holders of Preferred Securities to receive
Guarantee Payments under the Preferred Securities Guarantee.

     NOW, THEREFORE, in consideration of the purchase by each Holder of Common
Securities, which purchase the Guarantor hereby agrees shall benefit the
Guarantor, the Guarantor executes and delivers this Common Securities Guarantee
for the benefit of the Holders from time to time of the Common Securities.

                                    ARTICLE I

                                   DEFINITIONS

     SECTION 1.01   Definitions. As used in this Common Securities Guarantee,
each of the terms set forth below shall, unless the context otherwise requires,
have the following meaning. Each capitalized or otherwise defined term used but
not otherwise defined herein shall have the meaning assigned to such terms in
the Declaration as in effect on the date hereof.

     "Guarantee Payments" means the following payments or distributions, without
duplication, with respect to the Common Securities, to the extent not paid or
made by or on behalf of the Issuer pursuant to the Declaration or by the
Guarantor pursuant to the Indenture: (i) any accumulated and unpaid
Distributions required to be paid on the Common Securities, to the extent the
Issuer shall have funds available therefor, (ii) the Redemption Price with
respect to any Common Securities called for redemption by the Issuer to the
extent the Issuer shall have funds available therefor, and (iii) upon a
voluntary or involuntary dissolution and liquidation of the Issuer (other than
in connection with a Distribution of Debentures to Holders in exchange for
Common Securities as provided in the Declaration or the redemption of all such
Common Securities), the lesser of (a) the aggregate of the liquidation amount of
$25.00 per Common Security plus all accrued and unpaid Distributions on the
Common Securities to the date of payment, to the extent the Issuer shall have
funds available therefor and (b) the amount of assets of the Issuer remaining
available for Distribution to Holders upon a dissolution and liquidation of the
Issuer (in either case, the "Liquidation Distribution").

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     "Holder" means any holder, as registered on the books and records of the
Issuer, of any Common Securities.

     "Indenture" means the Indenture dated as of June 15, 1998, as amended or
supplemented from time to time, between Baltimore Gas and Electric Company and
The Bank of New York, as trustee thereunder.

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

     "Preferred Securities" means the preferred securities representing
undivided beneficial interests in the assets of the Issuer and having the rights
provided therefor in the Declaration.

     "Senior Indebtedness" means Senior Indebtedness as defined in the
Indenture.

     SECTION 1.02   Interpretation. In this Common Securities Guarantee,
unless the context otherwise requires:

          (a)  capitalized terms used in this Common Securities Guarantee but
     not defined in the preamble above have the respective meanings assigned to
     them in this Section 1;

          (b)  terms defined in the Declaration as at the date of execution of
     this Common Securities Guarantee have the same meaning when used in this
     Common Securities Guarantee unless otherwise defined in this Common
     Securities Guarantee;

          (c)  a term defined anywhere in this Common Securities Guarantee has
     the same meaning throughout;

          (d)  all references to "the Common Securities Guarantee" or "this
     Common Securities Guarantee" are to this Common Securities Guarantee as
     modified, supplemented or amended from time to time;

          (e)  all references in this Common Securities Guarantee to Articles
     and Sections are to Articles and Sections of this Common Securities
     Guarantee unless otherwise specified;

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          (f)  a reference to the singular includes the plural and vice versa;

          (g)  the masculine, feminine or neuter genders used herein shall
     include the masculine, feminine and neuter genders; and

          (h)  the word "or" is not exclusive, and the words "herein," "hereof"
     and "hereunder" refer to this Common Securities Guarantee as a whole.

                                   ARTICLE II

                                    GUARANTEE

     SECTION 2.01   Guarantee. The Guarantor irrevocably and unconditionally
agrees to pay in full to the Holders the Guarantee Payments (without duplication
of amounts theretofore paid by or on behalf of the Issuer pursuant to the
Declaration or by the Guarantor pursuant to the Indenture), as and when due,
regardless of any defense, right of set-off or counterclaim which the Issuer may
have or assert. The Guarantor's obligation to make a Guarantee Payment may be
satisfied by direct payment of the required amounts by the Guarantor to the
Holders, at the Guarantor's option or by causing the Issuer to pay such amounts
to the Holders.

     SECTION 2.02   Waiver of Notice and Demand. The Guarantor hereby waives
notice of acceptance of the Common Securities Guarantee and of any liability to
which it applies or may apply, presentment, demand for payment, any right to
require a proceeding first against the Issuer or any other Person before
proceeding against the Guarantor, protest, notice of nonpayment, notice of
dishonor, notice of redemption and all other notices and demands.

     SECTION 2.03   Obligations Not Affected. The obligations, covenants,
agreements and duties of the Guarantor under this Common Securities Guarantee
shall in no way be affected or impaired by reason of the happening from time to
time of any of the following:

          (a)  the release or waiver, by operation of law or otherwise, of the
     performance or observance by the Issuer of any express or implied
     agreement, covenant, term or condition relating to the Common Securities to
     be performed or observed by the Issuer;

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          (b)  the extension of time for the payment by the Issuer of all or any
     portion of the Distributions (other than an extension of time for payment
     of Distributions that results from an Extension Period on the Debentures as
     so provided in the Indenture), Redemption Price, Liquidation Distribution
     or any other sums payable under the terms of the Common Securities or the
     extension of time for the performance of any other obligation under,
     arising out of, or in connection with, the Common Securities;

          (c)  any failure, omission, delay or lack of diligence on the part of
     the Holders to enforce, assert or exercise any right, privilege, power or
     remedy conferred on the Holders pursuant to the terms of the Common
     Securities, or any action on the part of the Issuer granting indulgence or
     extension of any kind;

          (d)  the voluntary or involuntary liquidation, dissolution, sale of
     any collateral, receivership, insolvency, bankruptcy, assignment for the
     benefit of creditors, reorganization, arrangement, composition or
     readjustment of debt of, or other similar proceedings affecting, the Issuer
     or any of the assets of the Issuer;

          (e)  any invalidity of, or defect or deficiency in, the Common
     Securities;

          (f)  the settlement or compromise of any obligation guaranteed hereby
     or hereby incurred; or

          (g)  to the extent permitted by law, any other circumstance whatsoever
     that might otherwise constitute a legal or equitable discharge or defense
     of a guarantor (other than payments of the underlying obligation), it being
     the intent of this Section 2.03 that the obligations of the Guarantor
     hereunder shall be absolute and unconditional under any and all
     circumstances.

     There shall be no obligation of the Holders to give notice to, or obtain
the consent of, the Guarantor with respect to the happening of any of the
foregoing.

     SECTION 2.04   Rights of Holders. The Guarantor expressly acknowledges
that any Holder may institute a legal proceeding directly against the Guarantor
to enforce its

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rights under this Common Securities Guarantee, without first instituting a legal
proceeding against the Issuer or any other Person.

     SECTION 2.05   Guarantee of Payment. This Common Securities Guarantee
creates a guarantee of payment and not of collection (i.e., the guaranteed party
may institute a legal proceeding directly against the Guarantor to enforce its
rights under the Common Securities Guarantee without first instituting a legal
proceeding against any other person or entity). This Common Securities Guarantee
will not be discharged except by payment of the Guarantee Payments in full to
the extent not previously paid or upon Distribution to the Holders of the Common
Securities of the Debentures as provided in the Declaration.

     SECTION 2.06   Subrogation. The Guarantor shall be subrogated to all (if
any) rights of the Holders against the Issuer in respect of any amounts paid to
the Holders by the Guarantor under this Common Securities Guarantee; provided,
however, that the Guarantor shall not (except to the extent required by
mandatory provisions of law) be entitled to enforce or exercise any rights which
it may acquire by way of subrogation or any indemnity, reimbursement or other
agreement, in all cases as a result of payment under this Common Securities
Guarantee, if, at the time of any such payment, any amounts are due and unpaid
under this Common Securities Guarantee. If any amount shall be paid to the
Guarantor in violation of the preceding sentence, the Guarantor agrees to hold
such amount in trust for the Holders and to pay over such amount to the Holders.

     SECTION 2.07   Independent Obligations. The Guarantor acknowledges that
its obligations hereunder are independent of the obligations of the Issuer with
respect to the Common Securities and that the Guarantor shall be liable as
principal and as debtor hereunder to make Guarantee Payments pursuant to the
terms of this Common Securities Guarantee notwithstanding the occurrence of any
event referred to in subsections (a) through (g), inclusive, of Section 2.03
hereof.

                                   ARTICLE III

                                  SUBORDINATION

     SECTION 3.01   Ranking. This Common Securities Guarantee shall
constitute an unsecured obligation of the

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Guarantor and shall rank (a) subordinate and junior in right of payment to
all Senior Indebtedness of the Guarantor to the extent and in the manner set
forth in the Indenture with respect to the Debentures, and the provisions of
Article Eight of the Indenture will apply, MUTATIS MUTANDIS, to the
obligations of the Guarantor hereunder. The obligations of the Guarantor
hereunder do not constitute Senior Indebtedness (as defined in the Indenture)
of the Guarantor; (b) PARI PASSU with the senior most preferred stock now or
hereafter issued by the Guarantor and with any guarantee now or hereafter
issued by the Guarantor in respect of preferred stock of any Affiliate of the
Guarantor; (c) senior to any preferred or preference stock of the Guarantor
ranking junior to the senior most preferred or preference stock of the
Guarantor now or hereafter issued and (d) senior to the Guarantor's common
stock. If an Event of Default has occurred and is continuing under the
Declaration, the rights of the Holders to receive Guarantee Payments under
this Common Securities Guarantee shall be subordinated to the rights of the
holders of the Preferred Securities to receive payment of all amounts due and
owing under the terms of the Preferred Securities Guarantee.

     SECTION 3.02   PARI PASSU Guarantees. The obligations of the Guarantor
under this Common Securities Guarantee shall rank PARI PASSU with the
obligations of the Guarantor under (i) any similar guarantee agreements issued
by the Guarantor on behalf of the holders of preferred or capital securities
issued by any BGE Trust (as defined in the Indenture), (ii) the Indenture and
the Securities (as defined therein) issued thereunder, (iii) any expense
agreements entered into by the Guarantor in connection with the offering of
Trust Securities (as defined in the Indenture) by any BGE Trust (as defined in
the Indenture), and (iv) any other security, guarantee or other agreement or
obligation that is expressly stated to rank PARI PASSU with the obligations of
the Guarantor under this Common Securities Guarantee or with any obligation that
ranks PARI PASSU with the obligations of the Guarantor under this Common
Securities Guarantee.

                                   ARTICLE IV

                                   TERMINATION

     SECTION 4.01   Termination. This Common Securities Guarantee shall
terminate and be of no further force and effect upon full payment of the
Redemption Price or Liquidation Distribution for the Common Securities or upon
Distribution of the Debentures to the Holders of the Common

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Securities. This Common Securities Guarantee will continue to be effective or
will be reinstated, as the case may be, if at any time any Holder of the Common
Securities must restore payment of any sums paid under the Common Securities or
this Common Securities Guarantee.

                                    ARTICLE V

                                  MISCELLANEOUS

     SECTION 5.01   Successors and Assigns. All guarantees and agreements
contained in this Common Securities Guarantee shall bind the successors,
assigns, receivers, trustees and representatives of the Guarantor and shall
inure to the benefit of the Holders of the Common Securities then outstanding.
The Guarantor may not consolidate with or merge with or into, or sell, convey,
transfer or lease its properties and assets as an entirety or substantially as
an entirety (either in one transaction or a series of transactions) to, any
Person unless permitted under Article Eight of the Indenture. In connection with
a consolidation, merger or sale involving the Guarantor that is permitted under
Article Eight of the Indenture the Person formed by or surviving such
consolidation or merger or to which such sale, conveyance, transfer or lease
shall have been made, if other than the Guarantor, shall expressly assume all of
the obligations of the Guarantor hereunder.

     SECTION 5.02   Amendments. Except with respect to any changes which do not
materially adversely affect the rights of the Holders in any material respect
(in which case no consent of the Holders will be required), this Common
Securities Guarantee may only be amended with the prior approval of the Holders
of a majority in liquidation amount of the outstanding Common Securities. The
provisions of Article VI of the Declaration concerning meetings of the Holders
shall apply to the giving of such approval.

     SECTION 5.03.  Notices. All notices provided for in this Common Securities
Guarantee shall be in writing and delivered, telecopied or mailed by first class
mail, postage prepaid, as follows:

          (a)  if given to the Guarantor, to the address set forth below or such
     other address as the Guarantor may give notice of to the Holders:

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          Baltimore Gas and Electric Company
          750 East Pratt Street 16th floor
          Baltimore, Maryland 21202
          Facsimile No: (410) 783-3619
          Attention:  Treasurer

          (b)  if given to the Issuer, in care of the Administrative Trustee, at
     the Issuer's mailing address set forth below or such other address as the
     Issuer may give notice to the Holders:

          BGE Capital Trust II
          c/o Baltimore Gas and Electric Company
          750 East Pratt Street 16th floor
          Baltimore, Maryland 21202
          Facsimile No:  (410) 783-3619
          Attention:  Thomas E. Ruszin, Jr.

          (c)  if given to any Holder, at the address set forth on the books and
     records of the Issuer.

     All notices hereunder shall be deemed to have been given when received in
person, telecopied with receipt confirmed, or mailed by certified mail, postage
prepaid except that if a notice or other document is refused delivery or cannot
be delivered because of a changed address of which no notice was given, such
notice or other document shall be deemed to have been delivered on the date of
such refusal or inability to deliver.

     SECTION 5.04   Benefit. This Common Securities Guarantee is solely for
the benefit of the Holders and is not separately transferable from the Common
Securities.

     SECTION 5.05   Governing Law. THIS COMMON SECURITIES GUARANTEE SHALL BE
GOVERNED BY AND CONSTRUED AND INTERPRETED IN ACCORDANCE WITH THE LAWS OF THE
STATE OF NEW YORK.

     SECTION 5.06   Counterparts. This instrument may be executed in any number
of counterparts, each of which so executed shall be deemed to be an original,
but all such counterparts shall together constitute but one and the same
instrument.

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     THIS COMMON SECURITIES GUARANTEE is executed as of the day and year first
above written.


                                             BALTIMORE GAS AND ELECTRIC
                                             COMPANY,
                                                as Guarantor

                                             By:
                                                ------------------------------
                                                Name:
                                                Title:

                                             BGE CAPITAL TRUST II

                                             By:
                                                ------------------------------
                                                Name:
                                                Title:

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