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                                                                    Exhibit 4.13

                        ENVIRONMENTAL INDEMNITY AGREEMENT
                        ---------------------------------

         FOR VALUE RECEIVED, namely the loan of Four Million Five Hundred
Thousand and 00/100ths Dollars ($4,500,000.00), or any portion thereof, by
KEYBANK NATIONAL ASSOCIATION, a national banking association having a place of
business at One Canal Plaza, Portland, Maine 04101-4035 ("Bank") to AEROVOX
INCORPORATED, a Delaware corporation having a place of business at 740
Belleville Avenue, New Bedford, Massachusetts 02745 ("Borrower"), under the
terms and conditions of a certain Commercial Note of even date ("Note") given by
Borrower to Bank, which Note is secured by a First Leasehold Mortgage, Security
Agreement and Fixture Filing of even date ("Leasehold Mortgage") on Borrower's
leasehold estate evidenced by a Sublease dated January 4, 2000, between
Borrower, as Sublessee, and New Bedford Redevelopment Authority, as Sublessor
("Lease"), which Lease describes certain premises located at the New Bedford
Industrial Park, City of New Bedford, County of Bristol, and Commonwealth of
Massachusetts ("Premises"), Borrower does hereby unconditionally and irrevocably
agree to pay on demand to the Bank, and to reimburse, defend, hold harmless and
indemnify the Bank for, any and all liabilities, executions, awards, judgments,
claims, damages, demands, penalties, fines, actions, debts, suits, proceedings,
expenditures, indemnities, losses, charges or other amounts that are or may
become due from, claimed, asserted or entered against the Bank, including
reasonable attorneys' fees, in connection with, or arising directly or
indirectly out of, any hazardous, toxic, dangerous, radioactive, noxious or
unhealthful materials, substances, gases, and/or wastes, including, without
limitation, all of the following: (a) asbestos in any form; (b) urea
formaldehyde foam insulation; (c) transformers or other equipment which contain
dielectric fluid containing any level of polychlorinated biphenyls or (d) any
other chemical, material, gas, substance, or waste which is prohibited, limited,
or regulated by any federal, state, county, regional, local, or other
governmental authority, or which, even if not so prohibited, limited or
regulated, may or could pose a hazard to or be injurious to the environment,
health or safety of the occupants of the Premises, or which, even though not
posing a danger to the environment, health or safety, may or could constitute a
pollutant that could be subject to regulatory action by any Governmental
Authority (hereinafter "Hazardous Substances"); or (e) wetlands as
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defined pursuant to any applicable Environmental Laws (as defined herein)
situated in, over, upon, or under, or transported to, from, or near said
Premises; Borrower does hereby mean and intend to assume the obligation to pay,
and to indemnify and hold harmless the Bank for, without limitation, (1) all
costs incurred or expended by the Bank in connection with the removal of all
Hazardous Substances from said Premises, including, without limitation, all
costs of investigation, monitoring, remedial response, removal, restoration,
feasibility studies, remedial work, cleanup, engineering reports, and permit
acquisitions incurred in connection therewith; (2) all costs incurred and sums
expended by the Bank in determining the compliance of such removal with all
applicable regulations and standards; (3) all liability of, or expense to, the
Bank incurred as a result of the improper removal or disposal of Hazardous
Substances from said Premises, by whomever performed, or arising out of exposure
to Hazardous Substances of any individual while in or on said Premises, or
otherwise in connection with the existence or removal of, or failure to remove
any and all Hazardous Substances, on or from said Premises, together with (4)
all of the Bank's costs of defending against any action, suit or proceedings
brought or threatened by or on behalf of any Governmental Authority, individual
or entity allegedly injured as a result of the presence of Hazardous Substances
on said Premises, or emanating therefrom in any manner, whether such claim is
decided or settled adversely to or in favor of the Bank, and (5) any reasonable
attorneys' or consultants' fees incurred in connection with any of the foregoing
matters.

         Borrower does hereby further unconditionally assume and agree to
indemnify and make the Bank whole, as aforesaid, if the Bank should incur any
liability whatsoever under 38 M.R.S.A. (S)1301 et seq. (Pamph. 1987-1988), or
                                               -- ---
any similar law in effect in any state or jurisdiction where any Collateral is
located, or the Massachusetts Oil and Hazardous Materials Release Prevention and
Response Act, M.G.L. c. 21E, or the Massachusetts Hazardous Waste Management
Act, M.G.L. c. 21C, or the Comprehensive Environmental Response, Compensation,
and Liability Act of 1980, 42 U.S.C. (S)9601 et seq. (1983) ("CERCLA"), or the
                                             -- ---
Superfund Amendments and Reauthorization Act of 1986 ("SARA") or the Clean Water
Act, 33 U.S.C. (S)1251 et seq., or the Resource Conservation and Recovery Act
                       -- ---
("RCRA"), 42 U.S.C. 6901 et seq., or any regulation promulgated thereunder or
                         -- ---
any other local, state or federal regulation, law or ordinance relating in any
way to any Hazardous

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Substances, now or hereafter adopted (hereinafter "Environmental Laws"), because
of or arising out of the Bank's connection with the Premises. The foregoing
indemnity shall not apply to any claims concerning the presence of Hazardous
Substances on the Premises caused or created by Bank.

         The Bank shall not be required to pursue or exhaust its remedies
against any other party liable for the payment of any amounts or for any
performance for which Borrower herein agrees to indemnify the Bank, or for which
Borrower herein assumes liability or which the Borrower does hereby guaranty, or
against the property mortgaged or pledged as security for the payment of said
Note, but upon the incurring of any obligation, damage, penalty, loss, charge,
expense, execution, debt, suit, expenditure, cost or liability, the Bank may
immediately demand and enforce payment or performance from the Borrower pursuant
to this Environmental Indemnity Agreement. The obligations of the Borrower
hereunder shall survive the repayment in full of the Note, and shall remain in
full force and effect for all time. The obligations of the Borrower hereunder
shall bind Borrower's respective heirs, administrators, executors, personal
representatives, successors and assigns to the maximum extent permitted by law.

         Borrower hereby waives demand, notice and protest and waive all
recourse to suretyship and guarantorship defenses generally, including, but not
limited to, any extensions of time for payment or performance which may be
granted to any other liable party, any modifications or amendments to any of the
documents executed in connection with said Note, any act or omission to act by
or on behalf of the Bank, its successors and assigns, any release of security,
any release of a liable party or parties, and all other indulgences of any type
which may be granted by the Bank, its successors and assigns, to any other party
liable for the obligations assumed by Borrower herein, and does also agree to
pay all costs of enforcement hereof, and all costs of collection of amounts due
thereunder, including reasonable attorneys' fees incurred in connection
therewith; hereby meaning to waive any and all matters whatsoever whereby
Borrower would or might be released, in whole or in part, from the obligations
hereof.

         All amounts due hereunder shall bear interest from the initial date of
demand by the Bank, until paid, at a rate that shall be equal to the Default
Rate, as that term is defined under said Note.

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         Borrower hereby irrevocably agrees that any legal action or proceeding
arising out of or relating to this Environmental Indemnity Agreement may be
brought in any state or federal court in the State of Maine, at the election of
the Bank, its successors and assigns. By the execution and delivery hereof,
Borrower hereby irrevocably submits to the non-exclusive jurisdiction of any
such court in any such action or proceeding, and hereby waive the benefit of
jurisdiction derived from present or future domicile, and further waive personal
service of any and all process upon the undersigned in connection herewith, and
consent that any or all such service of process be made by registered or
certified mail, return receipt requested, postage prepaid, directed to Borrower
at the address given above (or such other address as Borrower may from time to
time provide to the Bank in writing), and any service so made shall be deemed to
have been completed three (3) days after the same shall have been so mailed.
Final judgment against Borrower in any such action, suit or proceeding shall be
conclusive and may be enforced in any other jurisdiction by suit on the
judgment, a certified or exemplified copy of which shall be conclusive evidence
of the fact.

         It is agreed that if this Environmental Indemnity Agreement be signed
by more than one person or entity, then the instrument becomes the joint and
several obligation of all the signers. This Environmental Indemnity Agreement is
to take effect as a sealed instrument.

Dated:  February 29th, 2000.

WITNESS:                               BORROWER:
                                       AEROVOX INCORPORATED

STANLEY B. KAY                         By: F. RANDAL HUNT
                                           Name: F. Randal Hunt
                                           Title: Vice President - Finance

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