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                                                                  EXHIBIT 10.2.1

                                 AMENDMENT NO. 2
                               TO CREDIT AGREEMENT


         AGREEMENT, dated as of October 8, 1999, 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 by Amendment
No. 1 to Credit Agreement, dated as of May 6, 1997, 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:

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

         SECTION 2. 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 of the Credit Agreement is amended by adding 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" to the end of such subsection 8.07(b).

         2.2      The definition of "Second Amendment Date" is added to Section
10 of the Credit Agreement in the correct alphabetical order and reads as
follows:

                  "SECOND AMENDMENT DATE" shall mean October 8, 1999."


         SECTION 3. 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;

         (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 both on the date hereof and on the date of (and after giving
effect to) satisfaction of the conditions precedent under the other clauses of
this Section 3 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 both on the date hereof and on the date of (and after
giving effect to) satisfaction of the conditions precedent under the other
clauses of this Section 3 with the same effect as though such representations
and warranties had been


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made on and as of each such date except to the extent that such representations
and warranties relate to a specified date;

         (c)      all required corporate and legal proceedings of the Borrower
with respect to this Agreement and the repurchase of the Senior Subordinated
Debt shall have been taken;

         (d)      the Agent shall have received such other agreements,
certificates and documents as the Agent may reasonably request in connection
with the transactions herein contemplated.


         SECTION 4. 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.

         SECTION 5. 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.

         SECTION 6. 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 a 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:

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By its signature below, each of the undersigned hereby (i) consents to the
foregoing amendment of the Credit Agreement, (ii) ratifies and confirms each of
the Security Documents and Guaranties to which it is a party and the security
interests and liens granted by it thereunder and (iii) agrees that pursuant to
the Guaranty to which it is a party it continues to guarantee the Obligations
(including, without limitation, any now or hereunder created Obligations under
the Credit Agreement as amended hereby) and the security interests and liens
granted by it under the Security Documents shall continue to secure such
Obligations.



HERMETIC SEAL CORPORATION

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


NORFOLK AVON REALTY TRUST

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


GLASSEAL PRODUCTS, INC.

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


SEALTRON ACQUISITION CORP.

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


SEALTRON, INC.

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


HCC INDUSTRIES INTERNATIONAL

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