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                                                                   Exhibit 10.68


                              I N V I S A, I N C.

                              AMENDED AND RESTATED
                       REGULATION S SUBSCRIPTION AGREEMENT

                        AMERICAN STOCK EXCHANGE PLACEMENT

                        400,000 UNITS AT $2.00 PER UNIT.
             EACH UNIT CONSISTING OF 1 COMMON SHARE $0.001 PAR VALUE
    AND 1 WARRANT TO PURCHASE 1 COMMON SHARE AT $2.00 PER SHARE; 1 WARRANT TO
 PURCHASE 1 COMMON SHARE AT $3.00 PER SHARE; AND 1 WARRANT TO PURCHASE 1 COMMON
                  SHARE AT $4.00 PER SHARE UNTIL JUNE 30, 2005

         THESE SECURITIES HAVE NOT BEEN REGISTERED WITH THE UNITED STATES
SECURITIES AND EXCHANGE COMMISSION OR THE SECURITIES COMMISSION OR ANY STATE
BECAUSE THEY ARE BELIEVED TO BE EXEMPT FROM REGISTRATION UNDER REGULATION S
PROMULGATED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE"ACT"). THIS
SUBSCRIPTION AGREEMENT SHALL NOT CONSTITUTE AN OFFER TO SELL NOR A SOLICITATION
OF AN OFFER TO BUY THE SECURITIES IN ANY JURISDICTION IN WHICH SUCH OFFER OR
SOLICITATION WOULD BE UNLAWFUL, THE SECURITIES ARE "RESTRICTED" AND MAY NOT BE
RESOLD OR TRANSFERRED OR EXEMPTION THEREFROM.

Dear Sirs:

1.       I hereby subscribe 125,000 Units of Invisa, Inc. at a purchase price of
         $2.00 per Unit for an aggregate investment in the amount of $ 250,000
         to cover the aggregate subscription price. This Amended and Restated
         Subscription Agreement supersedes and replaces any prior Subscription
         Agreement for Units of Invisa;

         The Purchaser agrees that this Subscription Agreement shall be executed
by Purchaser and either faxed to the Company at (941) 355-9373 or mailed to 4400
Independence Court, Sarasota, Florida, USA. The Purchaser agrees the
subscription payment shall be made by wire transfer to the account below:

         UBS SA
         Cornavin Branch
         Geneva - Switzerland
         Swift Code: UBSWCHZH12
         A/C Name: GM Capital Partners Ltd
         A/C No.: 0240-340.209.62 M Rubric Invisa 2.

2.       The Purchaser understands that the Company reserves the right to
reject, in whole or in part, any offer to subscribe, in the Company's
discretion, for any reason whatsoever and that no subscription may be withdrawn
once made.

3.       The Purchaser understands that this is a "best efforts only" offering,
and that the subscription, once accepted by the Company, will be used by the
Company as stated in their Use of Proceeds.

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                                      -2-

4.       The Purchaser understand that he has the right to demand registration
from the Company for both the common shares and the underlying shares
represented by the warrant. If the Purchaser provides the Company, in writing,
such a demand, the Company will file such a registration within 30 days of
receiving such a demand.

5.       The Purchaser hereby acknowledges that the Purchaser has had full
access to the Company's filings with the U.S. Securities and Exchange Commission
and the Company's book and records and all other information regarding the
Company.

6.       The Purchaser understands that an investment in the Company involves a
high degree of risk and is only suitable for sophisticated investors who are
willing and able to bear the associated risk of loss.

7.       The Purchaser represents and warrants that: (i) neither Purchaser nor
any person or entity for whom Purchaser is acting as a fiduciary is a U.S.
person as that term is defined in Rule 902(k) of Regulation S, to wit - a "U.S.
person" means any of the following:

         (a) Any natural person resident in the United States;

         (b) Any partnership or corporation organized or incorporated under the
             laws of the United States;

         (c) Any estate of which any executor or administrator is a U.S. person;

         (d) Any trust of which any trustee is a U.S. person;

         (e) Any agency or branch of a foreign entity located in the United
             States;

         (f) Any non-discretionary account or similar account (other than an
             estate or trust) held by a dealer or other fiduciary for the
             benefit or account of a U.S. person;

         (g) Any discretionary account or similar account (other than an estate
             or trust) held by a dealer or other fiduciary organized,
             incorporated, or (if an individual) resident in the United States;
             and

         (h) Any partnership or corporation if:

             (1) Organized or incorporated under the laws of any foreign
                 jurisdiction; and

             (2) Formed by a U.S. person principally for the purpose of
                 investing in securities not registered under the Act, unless it
                 is organized or incorporated, and owned, by "accredited
                 investors" who are not natural persons, estates or trusts.

(ii) at the time of the execution of this Subscription Agreement and the
Purchaser Questionnaire, Purchaser was outside of the United States; (iii) no
offer to purchase the Units was made to Purchaser or any of his/her/its
representatives in the United States; (iv) Purchaser agrees that he/she/it is
not a distributor or dealer, (v) Purchaser is purchasing the Units, including
the shares included as part of the Units, including the Warrants included as
part of the Units, and including the shares which may be issued under the
Warrants included as part of the Units (collectively hereinafter referred to as
the "Shares") for his/her/its own account or for the account of beneficiaries
for whom Purchaser has full investment discretion (in the event that Purchaser
is purchasing for a beneficiary, all of the representations and warranties set
forth herein are equally applicable to the beneficiary); (vi) Purchaser is
purchasing the Shares for investment purposes and not with a view towards
distribution. Purchaser has no present

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                                      -3-

intention to sell the Shares and Purchaser has no present arrangement (whether
or not legally binding) at any time to sell the Shares to or through any person
or entity; (vii) Purchaser will not engage in any activity for the purpose of,
or could be reasonably expected to have the effect of, conditioning the market
in the United States for any of the Shares sold hereunder; (viii) to the best of
the knowledge of Purchaser, neither the Company nor any person acting for the
Company, has conducted any "Directed selling efforts" as that term is defined in
Rule 902 of Regulation S; (ix) neither Purchaser nor any of his/her/its
affiliates or beneficiaries maintain, either directly or indirectly, any short
position in the common stock of the Company, and will not establish any such
short position; (x) during the one-year period commencing on the date of the
purchase of the Shares, the Purchaser will not offer or resell the Shares to a
U.S. person as defined in Regulation S regardless of whether such transactions
are within or outside the United States ("One-Year Period"), and any offers and
sales during the One-Year Period shall be made only in accordance with Rule 903
or Rule 904 of Regulation S, or pursuant to registration under the Act, or
pursuant to an exemption from the registration requirements of the Act as
determined by the Company's counsel. Further, the Shares will not be offered for
sale or resold by Purchaser (whether inside or outside the United States) for a
period of two years following the date of purchase of the Shares unless pursuant
to registration under the Act or pursuant to an exemption from registration
requirements of the Act as determined by the Company's counsel, and the
Purchaser agrees that the certificates representing the Shares will be subject
to stop-transfer instructions and a legend during said two-year period; (xi)
Purchaser has relied upon his/her/its independent investigation into the Company
and has been given no oral or written representations or assurances from the
Company or any of its representatives other than as set forth in this
Subscription Agreement or in the Company's Offering Document; (xii) Purchaser
acknowledges and agrees that no United States, federal or state agency has
passed upon or made any recommendation or endorsement of the Company, this
transaction or the purchase of the securities; and (xiii) he/she/it understands
it is the responsibility of any non-United States resident and citizen wishing
to purchase the Shares to satisfy himself/herself/itself as to full observance
of the laws of the Purchaser's relevant country or territory outside of the
United States of America in connection with any purchase, including obtaining
any required governmental or other consents or observing any other applicable
formalities.

8.       The Purchaser further represents and warrants that the Purchaser is an
"accredited investor" as such term is defined in Rule 501 of Regulation D
promulgated under the Act.

9.       In addition, the Purchaser represents and warrants that: (a)
his/her/its commitment to all investments is reasonable in relation to
his/her/its net worth; (b) he/she/it has the requisite knowledge or has relied
upon the advice of his/her/its own counsel, accountants or others, each of whom
qualifies as an Investor Representative with regard to all of the considerations
involved in making this investment; (c) he/she/it is aware that the right to
transfer the Shares is restricted as set forth herein; (d) he/she/it is aware
that the Company is in the development stage and has had limited sales and
revenue; (e) he/she/it has the financial ability to bear the economic risk of
the Shares and this investment in the Company (including the complete loss of
the entire investment), and has adequate means of providing for his/her/its
current and anticipated needs and personal contingencies, and no need for
liquidity with respect to his/her/its investment in the Company; and (f)
his/her/its overall commitment to investments which are not readily marketable
is not disproportionate to his/her/its net worth and this investment in the
Shares will not cause such overall commitment to become excessive.

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10.      In the event that this subscription is accepted, in whole or in part,
the Purchaser requests that the Shares be registered in the name(s) printed
below. Delivery will be made to the address printed below.

11.      The representations and warranties made by Purchaser in the Purchaser
Questionnaire are true and correct, may be fully relied upon by the Company as
being acquired and are expressly incorporated herein by reference and made a
part hereof.

Very truly yours,

Nautilus Technologies Ltd                                          July 22, 2003
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Print or type name                           Signature and Date signed

Method of Subscribing (check one):  Wire transfer                             X.
                                    Certified or Bank Check (enclosed)       __.
                                    Other (enclosed)                         __.

                                             c/o Gestrust SA
+41 22 731 57 70                             2 rue Thalberg, PO Box 1507
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Telephone Number                             Street Address

IBC 429 955                                  CH-1211 Geneva 1, Switzerland
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Identification No.                           City, State, and Zip Code
(i.e. - tax, registration or other
identification number)