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                                                                   EXHIBIT 10.76


                       INVESTMENT AGREEMENT MODIFICATION I

         This Investment Agreement Modification I ("Modification"), dated as of
July 21, 2003, by and among INVISA, INC., a Nevada corporation ("Company"), and
BARBELL GROUP, INC. ("Investor").

         Whereas, the parties entered into an Investment Agreement dated as of
May 9, 2003 ("Investment Agreement") providing, inter alia, that the Investor
shall invest up to one million dollars ($1,000,000) to purchase the Company's
common stock, $.001 par value per share (the "Common Stock");

         Whereas, contemporaneously with the execution and delivery of the
Investment Agreement, the parties executed and delivered a Registration Rights
Agreement pursuant to which the Company agreed to register the Common Stock to
be purchased by the Investor, the Company subsequently filed a Registration
Statement pursuant to the Registration Rights Agreement, and the Registration
Statement was declared effective on July 7, 2003; and

         Whereas, the Company wishes the Investor to purchase $100,000 of Common
Stock and the Investor is willing to do so upon the terms and conditions of this
Modification.

         Now therefore, the Company and the Investor hereby agree as follows:

         1.       Purchase and Sale of Common Stock. Simultaneously with the
execution of this Modification, upon the terms and conditions set forth herein,
the Company shall issue and sell to the Investor, and the Investor shall
purchase from the Company, up to that number of Shares having an aggregate
Purchase Price of $100,000.

         2.       Delivery of Put Notice. At any time within 30 days from the
date of this Modification, the Investor shall choose a Pricing Period, as
defined in the Investment Agreement. The Investor shall give written notice to
the Company of the Pricing Period and on the next Trading Day following the
Pricing Period, the Company shall delivery a Put Notice to the Investor which
states the Purchase Price of the Shares to be sold and the total number of
Shares to be sold based on the Purchase Price and the Put Amount, and for the
Pricing Period selected by Investor. If the Company does not deliver a Put
Notice as provided herein, the Investor may complete the Put Notice and fax the
Put Notice to the Company.


         3.       No Other Changes. Except as provided in this Modification,
none of the other terms and conditions of the Investment Agreement shall be
amended or modified and the Investment Agreement shall remain in full force and
effect.

         4.       Costs and Expenses. The costs and expenses of preparing this
Modification shall be borne by the Company and may be deducted from the Purchase
Price proceeds.

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         This Investment Agreement has been entered into and executed as of the
date first above written.

                                               INVISA, INC.



                                               By:
                                                   ------------------------

                                               BARBELL GROUP, INC.



                                               By:
                                                   ------------------------