Exhibit 4-A

      FIRST  SUPPLEMENTAL  INDENTURE,  dated as of the 1st day of August,  2000,
made and entered into by and between  METROPOLITAN  EDISON COMPANY,  corporation
organized  and  existing  under  the laws of the  Commonwealth  of  Pennsylvania
(hereinafter called the "Company"), and UNITED STATES TRUST COMPANY OF NEW YORK,
as Trustee under the Indenture hereinafter mentioned ("Trustee").

      WHEREAS,  the Company has heretofore executed and delivered to the Trustee
an  Indenture,  dated  as of May  1,  1999  (hereinafter  called  the  "Original
Indenture"),  to provide for the  issuance of  securities  in series and for the
initial series of securities to be known as the 7.35%  Subordinated  Debentures,
Series A, due 2039; and

      WHEREAS,   the  Original  Indenture,   as  the  same  may  be  amended  or
supplemented  from  time  to  time  by  indentures   supplemental   thereto,  is
hereinafter referred to as "the Indenture"; and

      WHEREAS,  the Original Indenture authorizes the Company and the Trustee to
enter into  supplemental  indentures  for the  purpose,  among  others,  to make
changes that do not adversely affect the rights of any Securityholder; and

      WHEREAS,  the  Company,  in the  exercise  of  the  powers  and  authority
conferred upon and reserved to it under the provisions of the Original Indenture
and pursuant to appropriate action of its Board of Directors, has fully resolved
and determined to make,  execute and deliver to the Trustee a First Supplemental
Indenture in the form hereof for the purposes herein provided; and

      WHEREAS,  the Company  represents  that all  conditions  and  requirements
necessary to make this First  Supplemental  Indenture,  in the form and upon the
terms hereof,  a valid,  binding and legal  instrument,  in accordance  with its
terms,  and for the purposes  herein  expressed,  have been done,  performed and
fulfilled, and the execution and delivery hereof, in the form and upon the terms
hereof, have been in all respects duly authorized.

      NOW,  THEREFORE,  Metropolitan  Edison Company,  in  consideration  of the
premises,  and  the  execution  and  delivery  by  the  Trustee  of  this  First
Supplemental Indenture and for other good and valuable  considerations,  receipt
of which is hereby  acknowledged,  hereby  covenants  and agrees to and with the
Trustee and its successors in the trust under the Indenture, as follows:

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                                    ARTICLE I

                             ADDITIONAL DEFINITIONS

      The following definition is added to the Indenture:

      "Trust Agreement" means the Amended and Restated Trust Agreement of Met-Ed
Capital Trust dated as of May 24, 1999 made by Met-Ed Capital as Grantor, Met-Ed
Preferred Capital II, Inc., and the Trustees named therein.

      "Trust  Security"  means a trust security issued under the Trust Agreement
representing  a  beneficial  interest  in  Met-Ed  Capital  Trust  equal  to and
representing a Preferred  Security and evidenced by a certificate  authenticated
in accordance with the Trust Agreement.

                                   ARTICLE II

      The following Section 6.13 is added to Article I of the Indenture:

Section 6.13. Rights of Enforcement.

      Notwithstanding  any  other  provision  of  this  Indenture,  if  a  Trust
Enforcement  Event (as defined in the Trust Agreement) occurs and is continuing,
or if any of the  circumstances  described  in Section  13.02(d)  of the Limited
Partnership Agreement occurs and is continuing, or if an Event of Default occurs
and is  continuing,  then  any  holder  of Trust  Securities  or any  holder  of
Preferred  Securities,  other than Met-Ed Capital  Trust,  may institute a legal
proceeding  directly  against the Company to enforce  the  Company's  obligation
under a corresponding  amount of Securities,  without first  instituting a legal
proceeding against any other Person.

                                  ARTICLE III.

                                  MISCELLANEOUS

      SECTION 3.01. For all purposes hereof, except as the context may otherwise
require, (a) all terms contained herein shall have the meanings given such terms
in, and (b) all references herein to sections of the Original Indenture shall be
deemed to be to such sections of, the Original  Indenture as the same heretofore
has been or hereafter may be amended by an indenture or indentures  supplemental
thereto.

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<PAGE>

      SECTION  3.02.  As amended  and  supplemented  by this First  Supplemental
Indenture,  the Original Indenture is in all respects ratified and confirmed and
the Original  Indenture  and this First  Supplemental  Indenture  shall be read,
taken and construed as one and the same instrument.

      SECTION  3.03.  The  parties  may sign any  number of copies of this First
Supplemental  Indenture.  Each signed copy shall be an original, but all of them
together represent the same agreement. Any signed copy shall be sufficient proof
of this First Supplemental Indenture.

      IN WITNESS WHEREOF, the undersigned,  being duly authorized, have executed
this First Supplemental  Indenture on behalf of the respective parties hereto as
of the date first above written.

                              METROPOLITAN EDISON COMPANY


                               By: /s/ T.G. Howson

                              Name:       T.G. Howson

                              Title:      Vice President and Treasurer

                              UNITED STATES TRUST COMPANY OF NEW YORK
                              as Trustee

                             By: /s/ Louis P. Young

                              Name:       Louis P. Young

                              Title:      Vice President

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