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                                                                   Exhibit 10.20



                FOURTH AMENDMENT TO CREDIT AND SECURITY AGREEMENT

     THIS FOURTH AMENDMENT TO CREDIT AND SECURITY AGREEMENT ("this Fourth
Amendment") is made and entered into as of the 28th day of December, 2001, by
and between BANK ONE, MICHIGAN, a bank chartered under the laws of Michigan
having an office at 611 Woodward Avenue, Detroit, Michigan 48226 ("Bank") and
TECHNICAL CONSUMER PRODUCTS, INC., a Delaware corporation (and successor by
merger to Technical Consumer Products, Inc., an Ohio corporation), with offices
at 300 Lena Drive, Aurora, Ohio 44202 ("Borrower").

                                    RECITALS:

     A. The Borrower and the Bank are parties to that certain Credit and
Security Agreement dated as of August 10, 2001 (as amended by two letter
amendments thereto dated, respectively, September 10, 2001 and October 15, 2001,
and a Confirmation of Assumption, Ratification and Amendment Agreement dated
October 18, 2001, the "Credit Agreement"), pursuant to which, INTER ALIA, the
Bank agreed, subject to the terms and conditions thereof, to advance Revolving
Loans (as this and other capitalized terms used herein but not otherwise defined
herein are defined in the Credit Agreement) to the Borrower.

     B. As of the close of business on December 28, 2001, the aggregate unpaid
principal balance of the Revolving Loans was $12,974,802.25, and the aggregate
undrawn stated amount of the Letters of Credit then outstanding was $-0-.

     C. The Borrower and the Bank have agreed to amend the Credit Agreement upon
and subject to the terms and conditions contained herein.


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                                   AGREEMENTS:

     NOW, THEREFORE, in consideration of the foregoing Recitals and the mutual
agreements hereinafter set forth, the Borrower and the Bank hereby agree as
follows:

     1. AMENDMENTS TO THE CREDIT AGREEMENT. Subject to the terms and conditions
of this Fourth Amendment, the Credit Agreement is hereby modified as follows:

     A. The definition of "Borrowing Base" in Section 1.1 (General Definitions)
is hereby amended and restated in its entirety to provide as follows:

          BORROWING BASE: At any time and from time to time, an amount equal to
     the sum of (i) an amount equal to the Account Percentage at such time of
     the face value of Borrower's Eligible Accounts at such time and (ii) the
     lesser of (a) $7,000,000 (provided, however, that, of said $7,000,000,
     in-transit Eligible Inventory, subject to the requirements of Section 5.13,
     below, shall not constitute more than $1,000,000 of the Eligible Inventory
     included in the Borrowing Base during the period commencing on the
     effective date of the Fourth Amendment to this Agreement through and
     including June 30, 2002) or (b) an amount equal to the Inventory Percentage
     at such time of Borrower's Eligible Inventory which is finished goods,
     valued at the lesser of cost or market value.

     B. The definition of "Debt" in Section 1.1 (General Definitions) is hereby
amended and restated in its entirety to provide as follows:

          DEBT: As applied to any Person, without duplication, (i) all
     indebtedness for money borrowed of such Person; (ii) all bonds, notes,
     debentures and similar debt securities of such Person; (iii) the deferred
     purchase price of capital assets or services which in accordance with GAAP
     would be shown on the liability side of the balance sheet of such Person
     (which, as to Borrower, shall be deemed to include, without limitation, the
     Borrower's monetary obligations under and pursuant to that certain amended
     and restated license agreement among Borrower, Andrzej Bobel and Practical
     Innovations, Inc. dated September 30, 2001); (iv) the face amount of all
     letters of credit issued for the account of such Person and, without
     duplication, all drafts drawn thereunder; (v) all obligations, contingent
     or otherwise, of such Person in respect of bankers' acceptances; (vi) all
     Debt of a second Person secured by any Lien on any property owned by such
     first Person, whether or not such Debt has been assumed; (vii) all
     Capitalized lease obligations of such Person and all Debt of such Person
     secured by purchase money Liens; (viii) the present value, determined on
     the basis of the implicit interest rate, of all basic rental obligations
     under all "synthetic" leases (i.e. leases accounted for by the lessee as
     operating leases under which the lessee is the "owner" of the leased
     property for Federal income tax purposes); (ix) all obligations of such
     Person to pay a specified purchase price for goods or services whether or
     not delivered or accepted, i.e., take-or-pay and similar obligations;



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     (x) all net obligations of such Person under any so-called `hedge', `swap',
     `collar', `cap' or similar interest rate or currency fluctuation protection
     agreements; (xi) the full outstanding balance of trade receivables, notes
     or other instruments sold with full recourse (and the portion thereof
     subject to potential recourse, if sold with limited recourse), other than
     in any such case any thereof sold solely for purposes of collection of
     delinquent accounts; (xii) the stated value, or liquidation value if
     higher, of all redeemable stock (or membership interest or other equity
     interest) of such Person; (xiii) any and all other obligations to pay
     money, including, without limitation, trade accounts payable and similar
     accrued expenses, and (xiv) all guaranty obligations of such Person;
     provided that the Debt of any Person shall in any event include (without
     duplication) the Debt of any other entity (including any general
     partnership in which such Person is a general partner) to the extent such
     Person is liable thereon as a result of such Person's ownership interest in
     or other relationship with such entity, except to the extent the terms of
     such Debt provide expressly that such Person is not liable thereon.

     C. The definition of "Maximum Revolving Credit" in Section 1.1 (General
Definitions) is hereby amended and restated in its entirety to provide as
follows:

          MAXIMUM REVOLVING CREDIT: At any time and from time to time, an amount
     equal to the lesser of (i) Twenty Million Dollars ($20,000,000) or (ii) the
     Borrowing Base at such time.

     D. Paragraph (B) of Section 4.2 (Eligible Inventory) is hereby amended and
restated in its entirety to provide as follows:

          (B) The Inventory is located at one of the locations listed on
     Schedule 6.1(E) attached hereto or in transit thereto; PROVIDED, HOWEVER,
     that from and after July 1, 2002, Inventory that is in transit shall not be
     Eligible Inventory;

     E. The last sentence of Section 2.9 (Unused Commitment Fee) is hereby
amended and restated in its entirety to provide as follows:

     The "unused portion of the Revolving Credit Facility" shall mean, as to any
     day, an amount equal to $20,000,000, MINUS an amount equal to the sum of
     (i) the aggregate outstanding principal amount of the Revolving Loans at
     the close of business of such day and (ii) the aggregate undrawn face
     amount of Letters of Credit outstanding at the close of business of such
     day.

     F. Clause (v) of Paragraph (B) of Section 7.1 (Affirmative Covenants) is
hereby amended and restated in its entirety to provide as follows:



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          (v) not later than 1:30 p.m. of each Banking Day, a borrowing
     certificate, in form and substance designated by Bank from time to time (a
     "Borrowing Base Certificate") duly completed, which, INTER ALIA, shall set
     forth the amount of Borrower's Debt owing to each of Shanghai Jensing
     Electron Electrical Equipment Co., Ltd. and Shanghai Zhen Xin Electronic
     Engineering Co., Ltd. as of such date;

     G. Paragraph (E) of Section 7.2 (Negative Covenants) is hereby amended and
restated in its entirety to provide as follows:

          (E) Declare or pay any dividend or other Distribution (other than
     dividends payable solely in shares of Stock) or purchase, acquire or retire
     any of its Stock outstanding at any time, other than by issuance of its
     Stock in exchange therefor, unless at the time of such Distribution (and
     after giving effect thereto), there exists (or would exist) no Possible
     Default or Event of Default;

     H. Paragraphs (J), (K) and (L) of Section 7.2 (Negative Covenants) are
hereby amended and restated in their entirety to provide as follows:

          (J) Allow the ratio of its Annualized Cash Flow to its Annualized Debt
     Service as at the end of any of the calendar quarters set forth below to be
     less than the ratio set forth opposite such quarter:

     Quarter Ending                              Minimum Ratio
     --------------                              -------------

     June 30, 2001                               3.50 to 1,

     September 30, 2001                          4.50 to 1,

     December 31, 2001                           3.75 to 1, and

     March 31, 2002 and thereafter               4.00 to 1;

          (K) Allow the ratio of (i) its Debt (other than trade payables and
     other similar accrued expenses, in each case arising in the ordinary course
     of business, unless evidenced by a note) as at the end of any calendar
     quarter ending on or after December 31, 2001 to (ii) its Annualized EBITDA
     as at the end of such calendar quarter to exceed 3.50 to 1;

          (L) Allow the ratio of (i) its Debt, MINUS the then unpaid principal
     balance of Subordinated Debt, to (ii) its Tangible Net Worth as at the end
     of any of the calendar quarters set forth below to exceed the ratio set
     forth opposite such quarter:



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     Quarter Ending                              Maximum Ratio
     --------------                              -------------

     June 30, 2001                               7.50 to 1,

     September 30, 2001                          6.50 to 1,

     December 31, 2001 and
     March 31, 2001                              4.75 to 1, and

     June 30, 2002 and thereafter                4.25 to 1;

     I. Paragraph (P) of Section 7.2 (Negative Covenants) are hereby amended and
restated in their entirety to provide as follows:

          (P) In any manner, (i) make (or give notice in respect of) any
     voluntary or optional payment or prepayment on, or redemption or
     acquisition for value of, or redeem, defease or otherwise satisfy prior to
     the scheduled maturity of, its Subordinated Debt, (ii) directly or
     indirectly, purchase or otherwise acquire any of its Subordinated Debt,
     (iii) make any payment on or in respect of the principal of or interest on
     Subordinated Debt, or take or fail to take any other action, in violation
     of the subordination provisions applicable to such Subordinated Debt, or
     (iv) permit the aggregate amount of indebtedness owing by Borrower to
     Shanghai Jensing Electron Electrical Equipment Co., Ltd. and Shanghai Zhen
     Xin Electronic Engineering Co., Ltd. to be less than a total of $3,931,000;

     J. The form of Amended and Restated Revolving Loan Note (the "Restated
Note") attached hereto as Attachment 1 is hereby substituted as a new Exhibit A
to the Credit Agreement.

     2. CONFIRMATION OF CONSENT. The Bank and the Borrower hereby confirm that
the Borrower heretofore advised the Bank of its intention to acquire
substantially all of the assets of enerSave data systems, Inc. and JRS
Technology, Inc., upon terms outlined generally by the Borrower to the Bank. In
connection with such acquisitions the Borrower represented (and hereby confirms
such representations) to the Bank that (a) at the time of the Borrower's
consummation of each such acquisition, no Possible Default or Event of Default
existed or, after giving effect to each such acquisition, arose, (b) after
giving effect to each such acquisition, the




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representations and warranties of the Borrower under the Credit Agreement remain
true and correct in all material respects, (c) the aggregate amount of
consideration paid or to be paid by the Borrower in connection with each such
acquisition (which shall include, without limitation, deferred purchase price,
non-competition agreement payments, consulting agreement payments, and patent
licensing payments) shall not exceed $500,000 (of which, as to one such
acquisition, $250,000 is to be paid in quarterly installments during the year
2002), and (d) the Borrower assumed no Debt in connection with either such
acquisition and the assets so acquired are free of all Liens, other than
Permitted Encumbrances. Based upon such representations and other information
supplied by the Borrower to the Bank, the Bank hereby confirms that, at the
Borrower's request, the Bank consented to both such acquisitions, subject to the
following: (i) the Borrower shall deliver to the Bank promptly following request
by the Bank a true and complete copy of the asset purchase agreement governing
each such acquisition, together with all other material agreements and other
documents to be executed and delivered by the Borrower in connection therewith,
and (ii) as to each such acquisition, the Borrower shall execute and deliver to
the Bank, within ten (10) Banking Days after request by the Bank, such
mortgages, security agreements and other documents as the Bank may reasonably
require to create or confirm and perfect a valid first priority Lien and
security interest in all such assets.

     3. EFFECTIVE DATE; CONDITIONS PRECEDENT. The representations, covenants and
consent set forth in Paragraph 2, above, are effective on the date hereof. The
modifications to the Credit Agreement set forth in Paragraph 1, above, shall not
be effective unless and until the date (the "Effective Date") on which the
Borrower shall have satisfied all of the following:

     A. On the Effective Date and after giving effect to the agreements and
waivers contained herein (i) there shall exist no Event of Default or Possible
Default, and the Borrower




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shall have delivered to the Bank written confirmation thereof dated as of the
Effective Date and (ii) the representations and warranties of the Borrower under
the Credit Agreement shall have been reaffirmed in writing as of the Effective
Date, subject only to variances therefrom acceptable to the Bank.

     B. The Borrower shall have delivered copies of resolutions of the board of
directors of the Borrower, certified by the secretary or an assistant secretary
thereof, authorizing the Borrower's execution and delivery of this Fourth
Amendment, the Restated Note required below and the performance of their terms.

     C. The Borrower shall have executed and delivered to the Bank the Restated
Note, which, from and after the Effective Date shall be deemed to be the
Revolving Note.

     D. Yan shall have executed and delivered to the Bank a confirmation of his
Guaranty in the form of Attachment 2 hereto.

     E. Shanghai Jensing Electron Electrical Equipment Co., Ltd. shall have
executed and delivered to the Bank a confirmation of its Intercreditor and
Subordination Agreement in the form of Attachment 3 hereto; and Shanghai Zhen
Xin Electronic Engineering Co., Ltd. shall have executed and delivered to Bank
an Amended and Restated Intercreditor and Subordination Agreement in the form of
Attachment 4 hereto.

     F. The Borrower shall have paid to the Bank, in immediately available
funds, an amendment fee in the amount of Five Thousand Dollars ($5,000).

     G. All legal matters incident to this Fourth Amendment and the consummation
of the transactions contemplated hereby shall be reasonably satisfactory to the
special counsel to the Bank.




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     H. The Bank shall have received such other certificates, opinions and
documents, in form and substance reasonably satisfactory to it, as the Bank or
its special counsel reasonably may request.

     4. OTHER LOAN DOCUMENTS. Any reference to the Credit Agreement or the
Revolving Note in the other Other Agreements shall, from and after the Effective
Date, be deemed to refer to the Credit Agreement, as modified by this Fourth
Amendment, and the Restated Note.

     5. CONFIRMATION OF DEBT. The Borrower hereby affirms all of its Bank Debt
to the Bank under the Credit Agreement and the Other Agreements, as the same are
modified hereby. The Borrower further acknowledges and agrees that as of the
Effective Date, it has no claims, defenses or set-off rights against the Bank,
and, as of the Effective Date, there are no claims, defenses or set-offs to the
enforcement by the Bank of the Bank Debt of the Borrower under the Credit
Agreement and the Other Agreements.

     6. NO OTHER MODIFICATIONS; SAME INDEBTEDNESS. Except as expressly provided
in this Fourth Amendment and in the Restated Note, all of the terms and
conditions of the Credit Agreement and the Other Agreements remain unchanged and
in full force and effect. The modifications effected by this Fourth Amendment
and by the other instruments contemplated hereby shall not be deemed to provide
for or effect a repayment and re-advance of any portion of the Revolving Loans
now outstanding, it being the intention of the Borrower and the Bank hereby that
the Bank Debt owing under the Credit Agreement, as amended by this Fourth
Amendment, be and hereby is the same Indebtedness as that owing under the Credit
Agreement immediately prior to the effectiveness hereof.




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     7. GOVERNING LAW; BINDING EFFECT. This Fourth Amendment shall be governed
by and construed in accordance with the laws of the State of Ohio and shall be
binding upon and inure to the benefit of the Borrower and the Bank and their
respective successors and assigns.

     IN WITNESS WHEREOF, the Borrower and the Bank have hereunto set their hands
as of the date first above written.


BANK                                        BORROWER
----                                        --------

BANK ONE, MICHIGAN                          TECHNICAL CONSUMER PRODUCTS, INC.



By: /s/ Randy R. Radik                      By: /s/ Ellis Yan
    -------------------------------             --------------------------------
    Randy R. Radik, Vice President              Ellis Yan, President





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