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                                                                    EXHIBIT 10.4

                                BARNES GROUP INC.

                     SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN

1.   Purpose

     The purpose of the Supplemental Executive Retirement Plan (the
"Supplemental Plan") is to provide supplemental pension benefits to selected
employees and certain Officers of Barnes Group Inc. (collectively
"Participants") who elect any form of contingent annuity under the Barnes Group
Inc. Salaried Retirement Income Plan (the "Pension Plan") under which a spouse
or former spouse is the contingent annuitant.

2.   Benefits

2.1  The Company will pay the amount described in the following paragraph to
     each person who meets the requirements of (A) and (B):

     (A) such person is either (i) an Officer on or after November 16, 1979, who
     either retires as an Officer under the Pension Plan with ten years of
     service with Barnes Group or a direct or indirect subsidiary of Barnes
     Group, or ceases to be an Officer due to disability, or (ii) an employee of
     Barnes Group Inc. who has been designated to participate in the
     Supplemental Plan by the Benefits Committee, and

     (B) such person is receiving retirement benefits under the Pension Plan
     pursuant to a contingent pensioner form of benefit under which the
     contingent pensioner is the Participant's spouse or former spouse.

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     The benefit payable to such Participants shall be a monthly supplemental
     annuity equal to (a) minus (b) where:

     (a)  equals the sum of: (i) the monthly retirement income payable to the
          Participant if he/she elected a straight life annuity under the
          Pension Plan; (ii) the monthly retirement income payable to the
          Participant under the Retirement Benefit Equalization Plan ("RBEP") if
          he/she elected a straight life annuity under the RBEP; and (iii) if
          the Participant is a participant in the Supplemental Senior Officer
          Retirement Plan ("SSORP"), the monthly retirement income payable to
          the Participant if he/she elected a straight life annuity under the
          SSORP; and

     (b)  equals the sum of: (i) the monthly pension benefits to which the
          Participant is entitled pursuant to the Pension Plan were he/she to
          elect the 50% contingent pensioner form of annuity, naming such spouse
          or former spouse as contingent pensioner; (ii) the monthly pension
          benefits to which the Participant is entitled pursuant to the RBEP
          were he/she to elect the 50% contingent pensioner form of annuity,
          naming such spouse or former spouse as contingent pensioner; and (iii)
          the monthly pension benefits to which the Participant is entitled
          pursuant to the SSORP were he/she to elect the 50% contingent
          pensioner form of annuity, naming such spouse or former spouse as
          contingent pensioner.

2.2  Benefits payable hereunder will be paid at the same time and in the same
     manner as benefits paid pursuant to the Pension Plan.

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3.   Administration

          The Benefits Committee shall administer the Supplemental Plan, and
shall have the same administrative powers relating to the Supplemental Plan as
it does with respect to the Pension Plan.

4.   General

4.1  The Supplemental Plan may be amended in whole or in part or terminated at
     any time by the Board of Directors of the Company, except that no such
     amendment or termination shall adversely affect the benefits payable to any
     person who has begun to receive benefits hereunder.

4.2  Benefits payable under the Supplemental Plan shall not be funded and shall
     be paid out of the general assets of the Company.

4.3  The Supplemental Plan shall be construed, administered, and enforced
     according to the laws of the State of Connecticut.

As amended by the Board of Directors May 16, 1997

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