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                                                                    EXHIBIT 10.4

                                 REVOLVING NOTE


$20,000,000.00                                                     March 6, 1998


         FOR VALUE RECEIVED, each of the undersigned, C.P. Clare Corporation, a
Massachusetts corporation ("Clare") and C.P. Clare N.V., a Belgian corporation
("C.P. Clare N.V.", and together with Clare, the "Borrowers"), hereby
unconditionally, and jointly and severally, promise to pay to the order of
BankBoston, N.A., formerly known as The First National Bank of Boston (the
"Lender") on June 30, 2001 the principal sum of Twenty Million Dollars
($20,000,000) or, if different, the aggregate unpaid principal amount of all
Revolving Loans made by the Lender pursuant to that certain Amended and Restated
Multicurrency Credit Agreement of even date herewith (as the same may be
amended, modified, extended, renewed, restated or supplemented from time to
time, the "Credit Agreement"), among the Borrowers, the various financial
institutions (including the Lender) as are, or may from time to time become,
parties thereto, and Bank of America National Trust and Savings Association, as
agent as provided therein, regardless of whether such principal amount is shown
on the schedule attached hereto (or any continuation thereof).

         The Borrowers further unconditionally, and jointly and severally,
promise to pay interest on the unpaid principal amount hereof from time to time
outstanding from the date hereof until maturity (whether by acceleration or
otherwise) and, after maturity and/or judgment, until paid, at the rate per
annum and on the dates specified in the Credit Agreement.

         Payments of both principal and interest are to be made in lawful money
of the United States of America in same day or immediately available funds to
the account designated by the agent pursuant to the Credit Agreement.

         This Note is one of the Revolving Notes referred to in, and evidences
Indebtedness incurred under, the Credit Agreement, to which reference is made
for a statement of the terms and conditions on which the Borrowers are permitted
and required to make prepayments and repayments of principal of the Indebtedness
evidenced by this Note and on which such Indebtedness may be declared to be
immediately due and payable. Unless otherwise defined, terms used herein have
the meanings provided in the Credit Agreement.

         This Note shall be in substitution for a replacement of that certain
Revolving Note dated September 11,1995 executed by the Borrowers to the order of
The First National Bank of Boston, in the original principal amount of Ten
Million Dollars ($10,000,000.00) (the "Original Note"). The indebtedness
evidenced by the Original Note is continuing indebtedness and nothing contained
herein shall be deemed to constitute
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payment, settlement or a novation of the Original Note or release or otherwise
adversely affect any lien or security interest securing such indebtedness

         ALL PARTIES HERETO, WHETHER AS MAKERS, ENDORSERS, OR OTHERWISE,
SEVERALLY WAIVE PRESENTMENT FOR PAYMENT, DEMAND, PROTEST AND NOTICE OF DISHONOR.

         THIS NOTE SHALL BE GOVERNED BY THE INTERNAL LAWS OF THE STATE OF
ILLINOIS.

                                         C.P. CLARE CORPORATION


                                         By: /s/  Arthur R. Buckland
                                                --------------------------------
                                            Title  President
                                                 -------------------------------

                                         C.P. CLARE N.V.


                                         By: /s/  Arthur R. Buckland
                                                --------------------------------
                                            Title  Director
                                                 -------------------------------


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