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                                                                   Exhibit 4.4.3

                            SECOND AMENDMENT TO
                           AMENDED AND RESTATED
                        REVOLVING CREDIT AGREEMENT



     THIS SECOND AMENDMENT TO AMENDED AND RESTATED REVOLVING CREDIT AGREEMENT
(this "Second Amendment") is made and entered into as of the 29th day of
December, 1995, by and among AEROVOX INCORPORATED, a Delaware corporation having
its principal place of business at 370 Faunce Corner Road, North Dartmouth,
Massachusetts 02747 (the "Borrower"), BHC AEROVOX, LTD., a corporation organized
under the laws of the United Kingdom (the "Guarantor") and THE FIRST NATIONAL
BANK OF BOSTON (the "Bank"), a national banking association having its principal
place of business at 100 Federal Street, Boston, Massachusetts 02110.

     WHEREAS, the Borrower, Aerovox Aero M, Inc., and the Bank entered into an
Amended and Restated Revolving Credit Agreement dated as of July 8, 1993 and
amended as of August 30, 1994 (as further amended and in effect from time to
time, the "Credit Agreement") pursuant to which the Bank extended credit to the
Borrower on the terms set forth therein;

     WHEREAS, Aerovox Aero M, Inc. has merged into its parent corporation,
Aerovox Incorporated;

     WHEREAS, BHC Aerovox, Ltd. ("BHC"), a wholly-owned Subsidiary of the
Borrower has agreed to guaranty the Obligations pursuant to (S)13 of the Credit
Agreement and to assume all of the obligations of the Guarantor under the Loan
Documents; and

     WHEREAS, the Bank, the Borrower and the Guarantor have agreed to amend the
Credit Agreement as hereinafter set forth;

     NOW, THEREFORE, for good and valuable consideration the receipt and
sufficiency of which is hereby acknowledged, the parties hereto agree as
follows:

     1.   Definitions.   Capitalized terms used herein without definition have
          -----------
the meanings ascribed to them in the Credit Agreement.

     2.   Amendment to (S)2.1 of the Credit Agreement. Section 2.1 of the Credit
          -------------------------------------------
Agreement is hereby amended to delete the amount "$15,000,000" appearing therein
and to substitute the amount "$14,360,000" in place thereof.

     3.   Amendment to (S)8.1 of the Credit Agreement. The table set forth in
          -------------------------------------------
(S)8.1 of theCredit Agreement is hereby deleted and the following substituted in
place thereof:
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                                       2


                    "Period                    Ratio
                     ------                    -----
               7/1/93 through 12/31/93        1.75:1
               1/1/94 through 3/31/95         1.50:1
               4/1/95 through 6/30/95         1.54:1
               7/1/95 through 9/30/95         1.50:1
               10/1/95 through 12/31/95       1.55:1
               1/1/96 through 3/31/96         1.75:1
               Thereafter                     1.50:1."

     4.   Amendment to (S)8.2 of the Credit Agreement. Section 8.2 of the Credit
Agreement is hereby deleted in its entirety and the following substituted in
place thereof:

          "8.2.   Interest Coverage Ratio. As of the end of any fiscal quarter
                  -----------------------
     commencing with the fiscal quarter ending September 30, 1993, the ratio of
     EBIT to Consolidated Total Interest Expense shall not be less than the
     stated ratio for the respective periods set forth below:

                    Period                     Ratio
               7/1/93 through 3/31/95         4.00:1
               4/1/95 through 6/30/95         3.66:1
               7/1/95 through 9/30/95         2.40:1
               10/1/95 through 12/31/95       2.00:1
               1/1/96 through 3/31/96         3.00:1
               Thereafter                     4.00:1."

     5.   Ratification, etc.
          ------------  ---
     Except as expressly amended or waived hereby, the Credit Agreement, the
other Loan Documents and all documents, instruments and agreements related
thereto are hereby ratified and confirmed in all respects and shall continue in
full force and effect. This Second Amendment and the Credit Agreement shall
hereafter be read and construed together as a single document, and all
references in the Credit Agreement or any related agreement or instrument to the
Credit Agreement shall refer to the Credit Agreement as amended by this Second
Amendment. By executing this Second Amendment where indicated below, the
Guarantor hereby ratifies and confirms its guaranty of the Obligations, and
acknowledges and consents to the terms of this Second Amendment.

     6.   GOVERNING LAW.
          -------------
     THIS SECOND AMENDMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH
THE LAWS OF THE COMMONWEALTH OF MASSACHUSETTS AND SHALL TAKE EFFECT AS A SEALED
INSTRUMENT IN ACCORDANCE WITH SUCH LAWS.

     7.   Counterparts.  This Second Amendment may be executed in any number of
          ------------
counterparts and by different parties hereto on separate counterparts, each of
which when so executed and delivered shall be an original, but all of which
counterparts taken together shall be deemed to constitute one and the same
instrument. Complete sets of counterparts shall be lodged with the Bank.
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                                       3


     8.   Effectiveness.  This Second Amendment shall become effective upon its
          -------------
execution and delivery by the respective parties hereto.

     9.   Entire Agreement.  THE CREDIT AGREEMENT AS AMENDED BY THIS SECOND
          ----------------
AMENDMENT REPRESENTS THE FINAL AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE
CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL
AGREEMENTS OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE
PARTIES.

     IN WITNESS WHEREOF, the undersigned have duly executed this Second
Amendment under seal as of the date first set forth above.

                           THE BORROWER:
                           ------------

                           AEROVOX INCORPORATED

                           By:    Ronald F. Murphy  
                              --------------------------
                           Title: Sr. V.P./Treasurer 
                                 -----------------------

                           THE GUARANTOR:
                           -------------

                           BHC AEROVOX, LTD.


                           By:    Ronald F. Murphy                          
                              --------------------------
                           Title: Director                    
                                  ----------------------


                           THE BANK:
                           --------

                           THE FIRST NATIONAL BANK OF
                           BOSTON


                           By:    Pauline J. Mozzone   
                              --------------------------
                           Title: Vice President                                
                                  ----------------------