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                                                                   Exhibit 10.51

                                     FOURTH
                              AMENDED AND RESTATED
                                 PROMISSORY NOTE
                              --------------------

$13,965,000                                                  New York, New York
                                                                  March 11, 1997
                                                                        --

         FOR VALUE RECEIVED, LEXINGTON COMPONENTS, INC., a Delaware corporation
(the "Debtor"), hereby unconditionally promises to pay to the order of CONGRESS
FINANCIAL CORPORATION, a California corporation (the "Payee"), at the offices of
Payee at 1133 Avenue of the Americas, New York, New York 10036, or at such other
place as the Payee or any holder hereof may from time to time designate, the
principal sum of THIRTEEN MILLION NINE HUNDRED SIXTY-FIVE THOUSAND AND NO/100
DOLLARS ($13,965,000) in lawful money of the United States of America and in
immediately available funds, in eighty-four (84) consecutive monthly
installments (or earlier as hereinafter referred to) on the first day of each
month commencing April 1, 1997, of which the first eight-three (83) installments
shall each be in the amount of ONE HUNDRED SIXTY-SIX THOUSAND TWO HUNDRED FIFTY
AND NO/100 DOLLARS ($166,250), and the last (i.e. eighty-fourth (84th))
installment shall be in the amount of the entire unpaid balance of this Note.

         Debtor hereby further promises to pay interest to the order of Payee on
the unpaid principal balance hereof at the Interest Rate. Such interest shall be
paid in like money at said office or place from the date hereof, commencing
April 1, 1997 and on the first day of each month thereafter until the
indebtedness evidenced by this Note is paid in full. Interest payable upon and
during the continuance of an Event of Default or following the effective date of
termination or non-renewal of the Financing Agreements shall be payable upon
demand.

         For purposes hereof, (a) the term "Interest Rate" shall mean, as to
Prime Rate Loans, a rate of one quarter of one (1/4%) percent per annum in
excess of the Prime Rate, and as to Eurodollar Rate Loans, a rate of two and
three-quarters (2 3/4%) percent per annum in excess of the Adjusted Eurodollar
Rate; PROVIDED, THAT, at Payee's option, the Interest Rate shall mean a rate of
two and one-quarter (2 1/4%) percent per annum in excess of the Prime Rate as to
Prime Rate Loans and a rate of four and three-quarters (4 3/4%) percent per
annum in excess of the Adjusted Eurodollar Rate as to Eurodollar Rate Loans,
upon and during the continuance of an Event of Default or after the effective
date of termination or non-renewal of the Financing Agreements, and (b) the term
"Prime Rate" shall mean the rate from time to time publicly announced by
CoreStates Bank, N.A., or its successors, at its office in Philadelphia,
Pennsylvania, as its prime rate, whether or not such announced rate is the best
rate available at such bank. Unless otherwise defined herein, all capitalized
terms used herein shall have the meanings

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assigned thereto in the Accounts Agreement (as hereinafter defined) and the
other Financing Agreements.

         The Interest Rate applicable to Prime Rate Loans payable hereunder
shall increase or decrease by an amount equal to each increase or decrease,
respectively, in the Prime Rate, effective on the first day of the month after
any change in the Prime Rate, based on the Prime Rate in effect on the last day
of the month in which any such change occurs. Interest shall be calculated on
the basis of a three hundred sixty (360) day year and actual days elapsed. In no
event shall the interest charged hereunder exceed the maximum permitted under
the laws of the State of New York or other applicable law.

         This Note is the "LCI Fourth Restated Note" issued pursuant to the
terms and provisions of the letter agreement re: Amendment to Financing
Agreements, dated as of the date hereof, between Debtor and Payee. The principal
amount of this Note represents the unpaid principal balance of $5,525,400
outstanding under that certain Third Amended and Restated Promissory Note, dated
August 21, 1996, in the original principal sum of $6,087,000 made by Debtor to
Payee PLUS the aggregate unpaid principal balance of $4,850,067 outstanding
under the New Equipment Term Note, dated January 30, 1997, made by Debtor to the
order of Payee, in the original principal amount of $500,000, the New Equipment
Term Note, dated July 1, 1996, made by Debtor to the order of Payee, in the
original principal amount of $500,000, the New Equipment Term Note, dated March
15, 1996, made by Debtor to the order of Payee, in the original principal amount
of $800,000, the New Equipment Term Note, dated December 15, 1995, made by
Debtor to the order of Payee, in the original principal amount of $600,000, the
New Equipment Term Note, dated October 11, 1995, made by Debtor to the order of
Payee, in the original principal amount of $700,000, the New Equipment Term
Note, dated September 13, 1995, made by Debtor to the order of Payee, in the
original principal amount of $600,000, the Term Promissory Note, dated August 1,
1995, made by Debtor to the order of Payee, in the original principal amount of
$1,000,000 and the New Equipment Term Note, dated June 26, 1995, made by Debtor
to the order of Payee, in the original principal amount of $1,300,000
(collectively, the "Existing Promissory Notes") PLUS an additional one-time
advance made on the date hereof by Payee to Debtor in the principal sum of
$3,589,533 (the "Additional Term Loan"). None of the outstanding indebtedness
evidenced by the Existing Promissory Notes shall be deemed extinguished by
Debtor's issuance or Payee's acceptance of this Note. This Note shall be deemed
to evidence the Additional Term Loan and to substitute for, and to amend and
restate in its entirety, the Existing Promissory Notes as to the indebtedness
previously evidenced thereby, and the Existing Promissory Notes shall be so
marked by Payee.

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         This Note is secured by the "Collateral" described in the Accounts
Financing Agreement [Security Agreement], dated January 11, 1990, by and between
Payee and Debtor, as amended (the "Accounts Agreement") and any agreement,
document or instrument now or at any time hereafter executed and/or delivered in
connection therewith or related thereto (the foregoing, as the same now exist or
may hereafter be amended, modified, supplemented, renewed, extended, restated or
replaced, are hereinafter collectively referred to as the "Financing
Agreements") and is entitled to all of the benefits and rights thereof and of
the Financing Agreements. At the time any payment is due hereunder, at its
option, Payee may charge the amount thereof to any account of Debtor maintained
by Payee.

         If any principal or interest payment is not made when due hereunder,
and such failure shall continue for three (3) days, or if any other Event of
Default (as defined in the Accounts Agreement) shall occur for any reason, or if
the Financing Agreements shall be terminated or not renewed for any reason
whatsoever, then and in any such event, in addition to all rights and remedies
of Payee under the Financing Agreements, applicable law or otherwise, all such
rights and remedies being cumulative, not exclusive and enforceable
alternatively, successively and concurrently, Payee may, at its option, declare
any or all of Debtor's obligations, liabilities and indebtedness owing to Payee
under the Financing Agreements (the "Obligations"), including, without
limitation, all amounts owing under this Note, to be due and payable, whereupon
the then unpaid balance hereof together with all interest accrued thereon, shall
forthwith become due and payable, together with interest accruing thereafter at
the then applicable rate stated above until the indebtedness evidenced by this
Note is paid in full, plus the costs and expenses of collection hereof,
including, but not limited to, reasonable attorneys' fees.

         Debtor (i) waives diligence, demand, presentment, protest and notice of
any kind, (ii) agrees that it will not be necessary for any holder hereof to
first institute suit in order to enforce payment of this Note and (iii) consents
to any one or more extensions or postponements of time of payment, release,
surrender or substitution of collateral security, or forbearance or other
indulgence, without notice or consent. Upon the occurrence and during the
continuance of any Event of Default, Payee shall have the right, but not the
obligation to setoff against this Note all money owed by Payee to Debtor.

         Payee shall not be required to resort to any Collateral for payment,
but may proceed against Debtor and any guarantors or endorsers hereof in such
order and manner as Payee may choose. None of the rights of Payee shall be
waived or diminished by any failure or delay in the exercise thereof.



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         Debtor hereby waives the right to a trial by jury and all rights of
setoff and rights to interpose counterclaims and cross-claims in any litigation
or proceeding arising in connection with this Note, the Accounts Agreement, the
other Financing Agreements, the Obligations or the Collateral, other than
compulsory counterclaims, the non-assertion of which would result in a permanent
waiver. Debtor hereby irrevocably consents to the non-exclusive jurisdiction of
the Supreme Court of the State of New York and of the United States District
Court for the Southern District of New York for all purposes in connection with
any action or proceeding arising out of or relating to this Note, the Accounts
Agreement, the other Financing Agreements, the Obligations or the Collateral and
further consents that any process or notice of motion or other application to
said Courts or any judge thereof, or any notice in connection with any
proceeding hereunder may be served (i) inside or outside the State of New York
by registered or certified mail, return receipt requested, and service or notice
so served shall be deemed complete five (5) days after the same shall have been
posted or (ii) in such other manner as may be permissible under the rules of
said Courts. Within thirty (30) days after such mailing, Debtor shall appear in
answer to such process or notice of motion or other application to said Courts,
failing which Debtor shall be deemed in default and judgment may be entered by
Payee against Debtor for the amount of the claim and other relief requested
therein.

         The execution and delivery of this Note has been authorized by the
Board of Directors of Debtor.

         This Note, the other Obligations and the Collateral shall be governed
by and construed in accordance with the laws of the State of New York and shall
be binding upon the successors and assigns of Debtor and inure to the benefit of
Payee and its successors, endorsees and assigns. If any term or provision of
this Note shall be held invalid, illegal or unenforceable, the validity of all
other terms and provisions hereof shall in no way be affected thereby.

         This Note may not be changed, modified or terminated orally, but only
by an agreement in writing signed by the Payee or the holder hereof.

         Whenever used herein, the terms "Debtor" and "Payee" shall be deemed to
include their respective successors and assigns.

                                           LEXINGTON COMPONENTS, INC.

                                           By:     Warren Delano
                                             ----------------------------
                                           Title:  President
                                                -------------------------


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