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                                                                 Exhibit 10.2.3

                                AMENDMENT NO. 4
                              TO CREDIT AGREEMENT

         AGREEMENT, dated as of August 18, 2000, among HCC INDUSTRIES INC., a
Delaware corporation (the "Borrower"), the lending institutions listed on the
signature pages hereof (collectively, the "Lenders") and FLEET CAPITAL
CORPORATION, as Agent (the "Agent").

         WHEREAS, the Borrower, the Lenders and the Agent are parties to that
certain Credit Agreement, dated as of February 14, 1997, as amended, pursuant
to which the Lenders have agreed, subject to certain terms and conditions, to
make revolving advances to the Borrower and to issue or to cause the issuance
of letters of credit for the account of the Borrower (such agreement being
referred to herein as the "Credit Agreement");

         WHEREAS, in connection with the contemplated repurchase by the
Borrower of certain senior subordinated notes, the Borrower has requested
that certain changes be made to the provisions contained in the Credit
Agreement, and the Lenders and the Agent are agreeable to making such
changes, subject to the terms and conditions herein contained.

         NOW, THEREFORE, the Borrower, the Lenders and the Agent hereby agree
as follows:

1.       SECTION CAPITALIZED TERMS. Capitalized terms used but not defined
herein shall have the respective meanings set forth in the Credit Agreement.

2.       SECTION AMENDMENTS TO CREDIT AGREEMENT. The Credit Agreement shall
be, and upon the fulfillment of the conditions set forth in Section 3 hereof
is, amended as follows:

         2.1 Section 8.07(b) of the Credit Agreement is amended by replacing
the phrase ", and except that the Borrower may repurchase up to $20,000,000
in face value of the Senior Subordinated Debt within 60 days of the Second
Amendment Date; PROVIDED that the aggregate amount paid by the Borrower shall
not exceed 65% of the face value of the Senior Subordinated Debt repurchased
by the Borrower" at the end of such Section 8.07(b) with the phrase ", and
except that the Borrower may repurchase up to $20,000,000 in face value of
the Senior Subordinated Debt on or before September 30, 2000; PROVIDED that
the aggregate amount paid by the Borrower shall not exceed 50% of the face
value of the Senior Subordinated Debt repurchased by the Borrower".

3.       SECTION EFFECTIVENESS. This Agreement and the amendments
contemplated hereby shall become effective when:

         (a) counterparts hereof have been duly executed and delivered to the
Agent on behalf of the Borrower, the Subsidiary Guarantors, the Lenders and
the Agent; and

         (b) the Agent shall be satisfied that, immediately after giving
effect to the amendments contemplated hereby, there shall exist no Default or
Event of Default and all representations and warranties contained herein, in
the Credit Agreement and in the other Loan Documents shall be true and
correct in all material respects with the same effect as though such
representations and warranties had been made on and as of such time except to
the extent that such representations and warranties relate to an earlier
specified date.

4.       SECTION COUNTERPARTS. This Agreement may be executed in
counterparts, each of which shall be an original, and all of which, taken
together, shall constitute a single instrument. This Agreement shall be
governed by, and construed in accordance with, the laws of the State of New
York.

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5.       SECTION REFERENCES TO CREDIT AGREEMENT. From and after the
effectiveness of this Agreement and the amendments contemplated hereby, all
references in the Credit Agreement to "this Agreement", "hereof', "herein",
and similar terms shall mean and refer to the Credit Agreement, as amended
and modified by this Agreement, and all references in other documents to the
Credit Agreement shall mean such agreement as amended and modified by this
Agreement.

6.       SECTION RATIFICATION AND CONFIRMATION. The Credit Agreement is
hereby ratified and confirmed and, except as herein agreed, remains in full
force and effect. The Borrower represents and warrants that both on the date
hereof and immediately after giving effect to the amendments herein
contemplated (i) all representations and warranties contained in any Loan
Document are and shall be true and correct in all material respects with the
same effect as though such representations and warranties had been made both
on and as of the date hereof and immediately after giving effect to the
amendments herein contemplated (except to the extent that such
representations or warranties expressly related to an earlier specified date)
and (ii) there exists and shall exist no Default or Event of Default.

         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to
be duly executed by their respective authorized officers as of the day and
year first above written.

                                HCC INDUSTRIES INC.

                                By:
                                   -------------------------------------------
                                Name:

                                Title:

                                FLEET CAPITAL CORPORATION, individually and as
                                Agent

                                By:
                                   -------------------------------------------
                                Name:
                                Title: