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                                                                    EXHIBIT 4.3



               FORM OF SERIES C EXCHANGE PASS THROUGH CERTIFICATE



                RELIANT ENERGY MID-ATLANTIC POWER HOLDINGS, LLC
                          SERIES C PASS THROUGH TRUST

               9.681% Series C Exchange Pass Through Certificate


                                     CUSIP:

                     Final Distribution Date: July 2, 2026

               evidencing a fractional undivided interest in a trust, the
               property of which includes certain notes secured by certain
               property leased to Reliant Energy Mid-Atlantic Power
               Holdings, LLC.

Certificate No.                          $_______ Fractional Undivided Interest


         THIS CERTIFIES THAT ____________________ for value received, is the
registered owner of a $___________ (___________________) ( _________ dollars)
Fractional Undivided Interest in the Reliant Energy Mid-Atlantic Power
Holdings, LLC-Series C Pass Through Trust (the "Pass Through Trust") created
pursuant to a Pass Through Trust Agreement dated as of August 24, 2000 (the
"Agreement") between Bankers Trust Company, as trustee (the "Pass Through
Trustee") and Reliant Energy Mid-Atlantic Power Holdings, LLC, a limited
liability company incorporated under Delaware law (the "Company"), a summary of
certain of the pertinent provisions of which is set forth below. To the extent
not otherwise defined herein, the capitalized terms used herein have the
meanings assigned to them in the Agreement. This Certificate is one of the duly
authorized Certificates designated as "9.681% Series C Exchange Pass Through
Certificates" (herein called the "Certificates"). This Certificate is issued
under and is subject to the terms, provisions and conditions of the Agreement,
to which Agreement the Holder of this Certificate by virtue of the acceptance
hereof assents and by which such Holder is bound. The property of the Pass
Through Trust includes certain Lessor Notes (the "Trust Property"). The Lessor
Notes are secured by a security interest in the Facility, and liability
thereunder is limited to the income and proceeds of such security.

         Subject to and in accordance with the terms of the Agreement, from
funds then available to the Pass Through Trustee, there will be distributed on
each January 2 and July 2 (a "Distribution Date"), commencing on July 2, 2001,
to the person in whose name this Certificate is registered at the close of
business on the day of the month which is 15 days preceding the Distribution
Date, an amount in respect of the Scheduled Payments on the Lessor Notes due on
such Distribution Date, the receipt of which has been confirmed by the Pass
Through Trustee, equal to the product of the percentage interest in the Pass
Through Trust evidenced by this Certificate and an amount equal to the sum of
such Scheduled Payments. Subject to and in accordance with the terms of the
Agreement, in the event that Special Payments on the Lessor




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Notes are received by the Pass Through Trustee, from funds then available to
the Pass Through Trustee, there shall be distributed on the applicable Special
Distribution Date, to the Person in whose name this certificate is registered
at the close of business on the day of the month which is 15 days preceding the
Special Distribution Date, an amount in respect of such Special Payments on the
Lessor Notes, the receipt of which has been confirmed by the Pass Through
Trustee, equal to the product of the percentage interest in the Pass Through
Trust evidenced by this Certificate and an amount equal to the sum of such
Special Payments so received. The Special Distribution Date shall be determined
as provided in the Agreement. If a Distribution Date or Special Distribution
Date is not a Business Day, distribution shall be made on the immediately
following Business Day. The Pass Through Trustee shall mail notice of each
Special Payment and the Special Distribution Date therefor to the Holders of
the Certificates.

         Distributions on this Certificate will be made by the Pass Through
Trustee by (i) if (A) The Depository Trust Company, a New York corporation
("DTC") is the Certificateholder of record of this Certificate, or (B) a
Certificateholder holds a Certificate or Certificates in an aggregate amount
greater than $10,000,000, or (C) a Certificateholder holds a Certificate or
Certificates in an aggregate amount greater than $1,000,000 and so requests to
the Pass Through Trustee, by wire transfer in immediately available funds to an
account maintained by such Certificateholder with a bank, or (ii) if none of
the above apply, by check mailed to such Certificateholder at the address
appearing in the Register, without the presentation or surrender of this
Certificate or the making of any notation hereon. Except as otherwise provided
in the Agreement and notwithstanding the above, the final distribution on this
Certificate will be made after notice mailed by the Pass Through Trustee of the
pendency of such distribution and only upon presentation and surrender of this
Certificate at the office or agency of the Pass Through Trustee specified in
such notice.

         Unless this certificate is presented by an authorized representative
of DTC to the Company or its agent for registration of transfer, exchange or
payment, and any certificate issued is registered in the name of Cede & Co. or
in such other name as is requested by an authorized representative of DTC (and
any payment is made to Cede & Co. or to such other entity as is requested by an
authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR
VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL in as much as the registered
owner hereof, Cede & Co., has an interest herein.

         Each Person who acquires or accepts this Certificate or an interest
herein will be deemed by such acquisition or acceptance to have represented and
warranted that either: (i) no Plan assets have been used to purchase this
Certificate or an interest herein or (ii) the purchase and holding of this
Certificate or interest herein are exempt from the prohibited transaction
restrictions of ERISA and the Code pursuant to one or more prohibited
transaction statutory or administrative exemptions.

         This Certificate shall be governed by and construed in accordance with
the laws of the State of New York.




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

         Unless the certificate of authentication hereon has been executed by
the Pass Through Trustee, by manual signature, this Certificate shall not be
entitled to any benefit under the Agreement or be valid for any purpose.

         IN WITNESS WHEREOF, the Pass Through Trustee has caused this
Certificate to be duly executed.



                                        RELIANT ENERGY MID-ATLANTIC
                                        POWER HOLDINGS, LLC-
                                        SERIES C PASS THROUGH TRUST


                               By:   Bankers Trust Company, as Pass Through
                                     Trustee


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


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                            [Reverse Of Certificate]

         The Certificates do not represent a direct obligation of, or an
obligation guaranteed by, or an interest in, the Company, the Owner Lessor, the
Owner Participant, the Equity Investor, the Equity Subsidiary, the Equity
Subsidiary Holding Company, the Pass Through Trust Company or the Pass Through
Trustee or any affiliate thereof. The Certificates are limited in right of
payment, all as more specifically set forth in the Agreement. All payments or
distributions made to Certificateholders under the Agreement shall be made only
from the Trust Property and only to the extent that the Pass Through Trustee
shall have received sufficient income or proceeds from the Trust Property to
make such payments in accordance with the terms of the Agreement. Each Holder
of this Certificate, by its acceptance hereof, agrees that it will look solely
to the income and proceeds from the Trust Property to the extent available for
distribution to such Holder as provided in the Agreement. This Certificate does
nor purport to summarize the Agreement and reference is made to the Agreement
for information with respect to the interests, rights, benefits, obligations,
proceeds and duties evidenced hereby. A copy of the Agreement may be examined
during normal business hours at the principal office of the Pass Through
Trustee, and at such other places, if any, designated by the Pass Through
Trustee, by any Certificateholder upon request.

         The Agreement permits, with certain exceptions therein provided, the
amendment thereof and the modification of the rights and obligations of the
Company and the rights of the Certificateholders under the Agreement at any
time by the Company and the Pass Through Trustee with the consent of the
Holders of Certificates evidencing Fractional Undivided Interests aggregating
not less than a majority in interest of the Fractional Undivided Interests
evidenced by all Certificates at the time Outstanding. Any such consent by the
Holder of this Certificate shall be conclusive and binding on such Holder and
upon all future Holders of this Certificate and of any Certificate issued upon
the transfer hereof or in exchange hereof or in lieu hereof whether or not
notation of such consent is made upon this Certificate. The Agreement also
permits the amendment thereof, in certain limited circumstances, without the
consent of the Holders of any of the Certificates.

         As provided in the Agreement and subject to certain limitations
therein set forth, the transfer of this Certificate is registrable in the
Register upon surrender of this Certificate for registration of transfer at the
offices or agencies maintained by the Pass Through Trustee in its capacity as
Registrar, or by any successor Registrar, in the Borough Of Manhattan, the City
of New York, duly endorsed or accompanied by a written instrument of transfer
in form satisfactory to the Pass Through Trustee and the Registrar duly
executed by the Holder hereof or such Holder's attorney duly authorized in
writing, and thereupon one or more new Certificates of authorized denominations
evidencing the same aggregate Fractional Undivided Interest in the Pass Through
Trust will be issued to the designated transferee or transferees.

         The Certificates are issuable only as registered Certificates without
coupons in minimum denominations of $100,000 Fractional Undivided Interest and
any integral multiples of $1,000 in excess thereof. As provided in the
Agreement and subject to certain limitations therein set forth, Certificates
are exchangeable for new Certificates of authorized denominations






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evidencing the same aggregate Fractional Undivided Interest in the Pass Through
Trust, as requested by the Holder surrendering the same.

         No service charge will be made for any such registration of transfer
or exchange, but the Pass Through Trustee shall require payment of a sum
sufficient to cover any tax or governmental charge payable in connection
therewith.

         The Pass Through Trustee, the Company, the Owner Lessor, the Registrar
and any agent of the Pass Through Trustee or the Registrar may treat the person
in whose name this Certificate is registered as the owner hereof for all
purposes, and neither the Pass Through Trustee, the Company, the Owner Lessor,
the Registrar nor any such agent shall be affected by any notice to the
contrary.

         The obligations and responsibilities created by the Agreement and the
Pass Through Trust created thereby shall terminate upon the distribution to
Certificateholders of all amounts required to be distributed to them pursuant
to the Agreement and the disposition of all property held as part of the Trust
Property.