<PAGE>   1


                SECOND AMENDED AND RESTATED REVOLVING CREDIT NOTE

$6,000,000                                                         July 11, 1997


     FOR VALUE RECEIVED, the undersigned CONNECTIVITY PRODUCTS
INCORPORATED, a Delaware corporation (the "Borrower"), hereby promises to pay to
the order of NBD Bank, a Michigan banking corporation (the "Bank") at the Bank's
head office at 611 Woodward Avenue, Detroit, Michigan 01608:

                      (a) prior to or on May 31, 2002 the principal amount of
              SIX MILLION AND NO/100 DOLLARS ($6,000,000) or, if less, the
              aggregate unpaid principal amount of the Revolving Credit Loans
              advanced by the Bank to the Borrower pursuant to the Amended and
              Restated Revolving Credit and Term Loan Agreement, dated as of May
              31, 1996 (as amended and in effect from time to time, the "Credit
              Agreement"), among the Borrower, the Bank and other parties
              thereto;

                      (b) the principal outstanding hereunder from time to time
              at the times provided in the Credit Agreement; and

                      (c) interest on the principal balance hereof from time to
              time outstanding from the Closing Date under the Credit Agreement
              through and including the maturity date hereof at the times and at
              the rate provided in the Credit Agreement.

     This Second Amended and Restated Revolving Credit Note ("this Note") is an
amendment and restatement of the Amended and Restated Revolving Credit Note,
dated as of August 27, 1996 (the "Restated Note"), which is an amendment and
restatement of the Revolving Credit Note, dated as of May 31, 1996, in each case
issued by the Borrower to the Bank. This Note is issued in substitution for, and
not in payment of, the Restated Note.

     This Note is one of the Revolving Credit Notes issued pursuant to
Section 2.4.1 of the Credit Agreement and evidences borrowings under, and has
been issued by the Borrower in accordance with the terms of, the Credit
Agreement. The Bank and any holder hereof is entitled to the benefits of the
Credit Agreement, the Security Documents and the other Loan Documents, and may
enforce the agreements of the Borrower contained therein, and any holder hereof
may exercise the respective remedies provided for thereby or otherwise available
in respect thereof, all in accordance with the respective terms thereof. All
capitalized terms used in this Note and not otherwise defined herein shall have
the same meanings herein as in the Credit Agreement.

     The Borrower irrevocably authorizes the Bank to make or cause to be made,
at or about the time of the Drawdown Date of any Revolving Credit Loan or at the
time of receipt of any payment of principal of this Note, an appropriate
notation on the grid attached to this Note, or the continuation of such grid, or
any other similar record, including computer records, reflecting the making of
such Revolving Credit Loan or (as the case may be) the receipt of such payment.
<PAGE>   2
                                      - 2 -


The outstanding amount of the Revolving Credit Loans set forth on the grid
attached to this Note, or the continuation of such grid, or any other similar
record, including computer records, maintained by the Bank with respect to any
Revolving Credit Loans shall be prima facie evidence of the principal amount
thereof owing and unpaid to the Bank, but the failure to record, or any error in
so recording, any such amount on any such grid, continuation or other record
shall not limit or otherwise affect the obligation of the Borrower hereunder or
under the Credit Agreement to make payments of principal of and interest on this
Note when due.

     The Borrower has the right in certain circumstances and the obligation
under certain other circumstances to prepay the whole or part of the principal
of this Note on the terms and conditions specified in the Credit Agreement.

     If any one or more of the Events of Default shall occur, the entire unpaid
principal amount of this Note and all of the unpaid interest accrued thereon may
become or be declared due and payable in the manner and with the effect provided
in the Credit Agreement.

     No delay or omission on the part of the Bank or any holder hereof in
exercising any right hereunder shall operate as a waiver of such right or of any
other rights of the Bank or such holder, nor shall any delay, omission or waiver
on any one occasion be deemed a bar or waiver of the same or any other right on
any further occasion.

     The Borrower and every endorser and guarantor of this Note or the
obligation represented hereby waives presentment, demand, notice, protest and
all other demands and notices in connection with the delivery, acceptance,
performance, default or enforcement of this Note, and assents to any extension
or postponement of the time of payment or any other indulgence, to any
substitution, exchange or release of collateral and to the addition or release
of any other party or person primarily or secondarily liable.

     THIS NOTE AND THE OBLIGATIONS OF THE BORROWER HEREUNDER SHALL FOR ALL
PURPOSES BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAW OF THE
COMMONWEALTH OF MASSACHUSETTS (EXCLUDING THE LAWS APPLICABLE TO CONFLICTS OR
CHOICE OF LAW). THE BORROWER AGREES THAT ANY SUIT FOR THE ENFORCEMENT OF THIS
NOTE MAY BE BROUGHT IN THE COURTS OF THE COMMONWEALTH OF MASSACHUSETTS OR ANY
FEDERAL COURT SITTING THEREIN AND THE CONSENT TO THE NONEXCLUSIVE JURISDICTION
OF SUCH COURT AND THE SERVICE OF PROCESS IN ANY SUCH SUIT BEING MADE UPON THE
BORROWER BY MAIL AT THE ADDRESS SPECIFIED IN SECTION 21 OF THE CREDIT AGREEMENT.
THE BORROWER HEREBY WAIVES ANY OBJECTION THAT IT MAY NOW OR HEREAFTER HAVE TO
THE VENUE OF ANY SUCH SUIT OR ANY SUCH COURT OR THAT SUCH SUIT IS BROUGHT IN AN
INCONVENIENT COURT.
<PAGE>   3
                                      - 3 -



     This Note shall be deemed to take effect as a sealed instrument under the
laws of the Commonwealth of Massachusetts.

     IN WITNESS WHEREOF, the undersigned has caused this Note to be signed in
its corporate name and its corporate seal to be impressed thereon by its duly
authorized officer as of the day and year first above written.

[Corporate Seal]

                                                CONNECTIVITY PRODUCTS
                                                INCORPORATED



                                                By:   /s/ James S. Harrington
                                                      -------------------------
                                                      Name: James S. Harrington
                                                      Title: President
<PAGE>   4
                                      - 4 -

<TABLE>
<CAPTION>
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                           Amount of                Amount of                Balance of
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                           Revolving             Principal Paid               Principal              Notation
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       Date               Credit Loan              or Prepaid                  Unpaid                Made By:
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<S>                       <C>                    <C>                         <C>                     <C>

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</TABLE>