Exhibit 10.4
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                                Amendment No. 3
                                    to the
                         1991 Stock Incentive Plan of
                                 AMETEK, Inc.

          WHEREAS, AMETEK, Inc. (the "Corporation") has adopted the 1991 Stock
Incentive Plan of AMETEK, Inc. (the "Plan"); and

          WHEREAS, Section 19 of the Plan permits the Corporation to amend the
Plan; and

          WHEREAS, the Corporation now desires to amend the Plan in certain
respects;

          NOW THEREFORE, the Plan is hereby amended as follows:
          follows:

          NOW THEREFORE, the Plan is hereby amended as follows:

          1.  The first sentence of Section 13 of the Plan is amended to read,
in its entirety, as follows:

          "If a holder of an Option and/or Rights shall voluntarily or
involuntarily leave the employ of the Corporation and its Affiliates, the Option
and Rights of such holder shall terminate forthwith, except that the holder
shall have until the expiration of 3 months (3 business days in the case of
Incentive Stock Options granted before November 20, 1996)from the cessation of
the holder's employment with the Corporation and its Affiliates (without 

 
regard to any period of severance) to exercise any unexercised Option and/or
Rights the holder could have exercised on the day on which he left the employ of
the Corporation and Affiliates."

          2.  The provisions of this Amendment No. 3 shall be effective for
terminations occurring on and after November 20, 1996.

          IN WITNESS WHEREOF, AMETEK has caused these presents to be executed,
in its corporate name, by its duly authorized officer, and its corporate seal to
be affixed on this 12th day of December, 1996.

                                      AMETEK, Inc.

                                      By:/s/ Robert W. Yannarell
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                                         Robert W. Yannarell

Attest:

/s/ Donna F. Winquist
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Donna F. Winquist
(Seal)