Exhibit 10.6 Senior Secured Promissory Note


    

       

      SENIOR
        SECURED PROMISSORY NOTE

       

      February
        28, 2007

      Sarasota,
        Florida 

       

      FOR
        VALUE
        RECEIVED, the undersigned, INVISA,
        INC.,
        a
        Nevada corporation (“Borrower”)
        having
        an address at 6935 15th
        Street,
        Suite 120, Sarasota, Florida, 34243 promises to pay to the order of Centurian
        Investors, Inc, a Delaware corporation (“Lender”),
        having an office at 290 Cocoanut Avenue, Sarasota, Florida, or such other
        place
        as the Lender may designate in writing, the principal amount up to and not
        to
        exceed ONE HUNDRED FIFTY HOUSAND United States Dollars (U.S. $150,000.00),
        to
        the extent advanced hereunder and then outstanding, with interest on the
        unpaid
        principal balance from the date of this Senior Secured Promissory Note (this
        “Promissory
        Note”),
        until
        paid, at the Interest Rate (as hereinafter defined) provided herein.


       

      1.  Rate
        of Interest.
        The
        outstanding principal balance of this Promissory Note shall bear interest
        at ten
        percent (10%) per annum (the “Interest
        Rate”).
        

       

      2.  Date
        and Time of Payment.
        The
        outstanding principal balance of this Promissory Note, together with all
        accrued
        and unpaid interest, shall be paid in full on earlier to occur of (a) the
        Maturity Date or (b) the date of termination of this Promissory Note, whether
        by
        its terms, by prepayment, or by acceleration. All amounts outstanding hereunder
        shall constitute Borrower’s obligations hereunder, and such obligations include
        without limitation all principal, interest (including all interest which
        accrues
        after the commencement of any case or proceeding by or against Borrower in
        bankruptcy whether or not allowed in such case or proceeding), expenses,
        attorneys’ fees and any other sum chargeable to Borrower hereunder and owing to
        Lender under this Promissory Note (all such obligations and all other
        obligations of Borrower under this Promissory Note ,(the “Obligations”).
        No
        principal amount of this Note paid or prepaid may be reborrowed. 

       

      3.  Default
        Rate.
        Notwithstanding Section
        1,
        after
        the occurrence of any Event of Default and for so long as such Event of Default
        continues, and in any event from and after the Maturity Date, all principal,
        interest and other amounts payable under this Promissory Note shall bear
        interest until paid in full at a rate of interest equal to four percent (4%)
        above the per annum rate otherwise applicable hereunder (the “Default
        Rate”).
        

       

      4.  Computation
        of Interest.
        Interest on the principal amount hereof and all other Obligations shall be
        computed on the basis of a 360-day year, and shall be charged for the actual
        number of days elapsed during any month
        or
        other accrual period.

       

      5.  Manner
        of Payment.
        All
        payments by Borrower in respect of any Obligations shall be made without
        deduction, defense, set off or counterclaim, free and clear of all taxes
        delivered to Lender. 

       

      6.  Maturity.
        To the
        extent not sooner due and payable in accordance with this Promissory Note
        , the
        Obigations shall be due and payable six months from the date hereof
        (the
“Maturity
        Date”).
        

       

      7.  Application
        of Payments.
        All
        payments shall be applied to amounts then due and payable in the following
        order: (a) to Lender’s costs and expenses reimbursable in connection herewith;
        (b) to interest accrued on the outstanding principal balance of this Promissory
        Note; (c) to the principal amount hereof; and (d) to all other Obligations,
        or
        in such other manner as Lender shall determine in its sole and exclusive
        discretion.

       

      8.  Procedure
        for Borrowing and Use of Proceeds. The
        proceeds of this Promissory Note shall be funded in multiple advances (each,
        an
“Advance”)
        by
        Lender to Borrower in the amounts and on such dates as determined by Lender
        based on requests from Borrower. Borrower shall give Lender notice requesting
        that Lender make an Advance in accordance herewith specifying (a) the Borrowing
        Date, (b) the amount requested and (c) a detailed, itemized list of the use
        of
        such Advance. Upon receipt of such notice from Borrower, Lender shall determine,
        in its sole and exclusive discretion, whether it shall make such amount
        available to Borrower on the Borrowing Date. Upon each Advance, Lender shall
        record each Advance on Schedule I to this Promissory Note. For purposes of
        this
        Section 8, the Borrowing Date shall mean any business day specified in the
        notice pursuant to this Section 8 as a date on which Borrower requests Lender
        to
        make a loan hereunder. An initial Advance of FORTY FIVE THOUSAND DOLLARS
        ($45,000) shall be made simulateously with the execution of this Promissory
        Note. The obligation of Lender to make each subsequent Advance following
        the initial Advance hereunder
        is subject to the Lenders approval of the loan request made by Borrower in
        accordance with this Section 8 and shall be funded in the sole and exclusive
        discretion of Lender. 

       

      9.  Security.
        This
        Promissory Note shall be secured by (i) Twenty Million (20,000,000) shares
        of
        common stock of Borrower to be issued as of the date hereof and held in escrow
        and a continuing first priority security interest in all of Borrower’s right,
        title, and interest in and to, all property of Borrower (collectively, the
        “Collateral”),
        as
        more specifically set forth in the Security Agreement executed by Borrower
        in
        favor of Lender as of the date hereof, in substantially the form attached
        hereto
        as Exhibit A (the “Security Agreement”).

       

        Priority This
        Promissory Note shall be a senior obligation of Borrower, and for so long
        as
        this Promissory Note shall be outstanding, (i) Borrower shall be prohibited
        from
        incurring any and all future indebtedness without the prior written consent
        of
        Lender and (ii) any and all future indebtedness approved by Borrower in writing
        shall be deemed subordinate and inferior to, all respective right, title
        and
        interest of Lender, in, to and under this Promissory Note, this Security
        Agreement and any and all documents and instruments evidencing, securing
        or
        otherwise relating to this Promissory Note. 

       

      10.  Representations
        and Warranties.
        Borrower
        makes the following representations and warranties to Lender, which
        representations and warranties shall be true, correct, and complete as of
        the
        date hereof and shall survive the execution and delivery of this Promissory
        Note. 

       

      (a)  Due
        Organization and Qualification.
        Borrower is duly organized and validly existing and in good standing under
        the
        laws of the jurisdiction of its organization and qualified to do business
        in any
        jurisdiction where it is required to be so qualified, and has all requisite
        power and authority to (i) own its assets and carry on its business, and
        (ii)
        execute, deliver and perform its Obligations. 

       

      (b)  Due
        Authorization; No Conflict.
        The
        execution, delivery, and performance by Borrower of this Promissory Note
        has
        been duly authorized by all necessary action on the part of Borrower. This
        Promissory Note has been duly executed and delivered by Borrower. The execution,
        delivery, and performance by Borrower of this Promissory Note and the
        consummation of the transactions contemplated hereby, do not and will not
        (i)
        violate in any material respect any provision of federal, state, provincial
        or
        local law or regulation applicable to Borrower, its organizational documents,
        or
        any order, judgment, or decree of any court or other governmental authority,
        (ii) conflict with, result in a breach or termination of, or constitute (with
        due notice or lapse of time or both) a default under any material contractual
        obligation of Borrower, (iii) result in or require the creation or imposition
        of
        any lien of any nature whatsoever upon any properties or assets of Borrower,
        other than liens or security interests in favor of Lender, or (iv) require
        any
        approval of any of Borrower’s stockholders or any approval or consent of any
        other person or entity, other than consents or approvals that have been obtained
        and that are still in force and effect. The execution, delivery, and performance
        by Borrower of this Promissory Note do not and will not require any registration
        with, consent, or approval of, or notice to, or other action with or by,
        any
        governmental authority, other than consents or approvals that have been obtained
        and that are still in force and effect. This Promissory Note when executed
        and
        delivered by Borrower will be the legally valid and binding obligation of
        Borrower, enforceable against Borrower in accordance with its term, except
        as
        enforcement may be limited by equitable principles or by bankruptcy, insolvency,
        reorganization, moratorium, or similar laws relating to or limiting creditors’
rights generally. 

       

      (c)  No
        Litigation.
        No
        litigation, investigation or proceeding of or before any arbitrator or
        government authority is (i) pending or, to the knowledge of Borrower, threatened
        with respect to this Promissory Note or the Collateral or any of the
        transactions contemplated hereby or (ii) pending or, to the knowledge of
        Borrower, threatened by or against Borrower, its properties or revenues which,
        if adversely determined, would have a material adverse effect on its business,
        operations, property or financial condition, when taken as a whole.


       

      (d)  No
        Default.
        Borrower is not in default under or with respect to any contractual obligation
        and no event of default has occurred or is continuing with respect to
        Borrower.

       

      (e)  Taxes.
        Borrower
        has filed or caused to be filed all tax returns required to be filed by it
        and
        has paid all taxes due and payable on said returns or on any assessments
        made
        against Borrower or any of its property. All other taxes, fees or other charges
        on Borrower or any of its property by any governmental authority have been
        paid
        and no tax liens have been filed. 

       

      12.
        Covenants
        of Borrower. As
        of the
        date hereof and so long as the Obligations hereunder shall be
        outstanding:

       


      
        
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      (a)
        Borrower will
        preserve and keep in force and effect, its corporate existence and all licenses
        and permits necessary to the proper conduct of its business;

       

      


      (b)
        Borrower will promptly pay and discharge, all lawful taxes, assessments,
        charges
        or levies imposed upon Borrower, or upon or in respect of all or any part
        of the
        property or business of Borrower, all trade accounts payable in accordance
        with
        usual and customary business terms and all claims for work, labor or materials,
        which if unpaid might become a lien or charge upon any property of Borrower;
        provided,
        Borrower shall not be required to pay such tax, assessment, charge, levy,
        account payable or claim if (i) the validity, applicability or amount thereof
        is
        being contested in good faith by appropriate action or proceeding which will
        prevent the forfeiture or sale of any property of Borrower, and (ii) Borrower
        shall set aside on its books, reserves deemed by it to be adequate with respect
        thereto;

      


      (c)
        Borrower will promptly comply with all laws, ordinances or governmental rules
        and regulation to which it is subject, the violations of which would materially
        or adversely affect its properties, business, prospects, profits or condition
        or
        would result in any material lien or charge upon any property of
        Borrower;

      


      (d)
        Borrower will maintain, preserve and keep its properties which are used or
        useful in the conduct of its business in good repair and working order;


      


      (e)
        Borrower will not create, assume or incur or in any manner become liable
        with
        respect of any indebtedness except this Promissory Note and any indebtedness
        of
        Borrower incurred prior to the date hereof.

      


      (f)
        Borrower will not create or incur any mortgage, pledge, security interest,
        encumbrance, lien or charge of any kind (a “Lien”) on its or its property or
        assets, whether now owned or hereinafter acquired, or upon any income or
        profits
        therefrom except 

      


      (i) Liens
        for
        property taxes and assessments or levies and liens that are not yet due and
        payable; 

      


      (ii) Liens
        of
        or resulting from any judgment or award, the time for appeal or petition
        for
        rehearing of which shall not have expired or in respect of which the Company
        shall in good faith be prosecuting an appeal or proceeding for a review and
        in
        respect of which a stay of execution pending such appeal or proceeding for
        review shall have been secured; or 

      


      (iii) Liens
        or
        priority claims (A) incidental to the conduct of business, (B) created by
        any
        material agreement of Borrower entered into prior to and currently in effect
        as
        of the date hereof or (C) the ownership or lease of properties and assets
        and
        not in connection with the borrowing of money, provided,
        in each
        case, the obligation secured is not overdue, or if overdue, is being contested
        in good faith by appropriate actions or proceedings and provided,
        further
        that
        Borrower shall have received the prior written consent of Lender to any Lien
        described in (A) or (C) above; or


      
        
          
 

          
          

        

        
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      13. Events
        of Default; Remedies; Acceleration.
        (a) The
        occurrence of any one or more of the following events (regardless of the
        reason
        therefor) shall constitute an “Event
        of Default”
        hereunder: 

       

      (i)
        Borrower fails to make any payment of outstanding principal balance of this
        Promissory Note , or interest thereon, or any of the other Obligation when
        due
        and payable; , 

       

      (ii)
        Any
        representation or warranty of Borrower made in this Promissory Note, the
        Security Agreeent, or any other document made by or on behalf of Borrower
        in
        connection herewith and the transactions contemplated hereby proves to have
        been
        false or incorrect in any material respect or Borrower shall fail to comply
        in
        all respects with any covenant herein or therein;

       

      (iii)
        Borrower shall violate any provision of this Promissory Note, the Security
        Agreement or any other document made by or on behalf of Borrower in connection
        herewith and the transactions contemplated hereby, including, without
        limitiation, failure to comply with the terms and provisions of Section 8
        of
        this Promissory Note;

       

      (iv)
        A
        case or proceeding is commenced against Borrower seeking a decree or order
        (i)
        under Title 11 of the United States Bankruptcy Code (11 U.S.C. §§101
et
        seq.,
        as
        amended, and any successor statute, the “Bankruptcy
        Code”),
        or
        any other applicable federal, state or foreign bankruptcy or other similar
        law,
        rule or regulation, (ii) appointing a custodian, receiver, liquidator, assignee,
        trustee or sequestrator (or similar official) for Borrower or for any
        substantial part of Borrower’s assets, or (iii) ordering the winding-up or
        liquidation of the affairs of s Borrower, and such case or proceeding shall
        remain undismissed or unstayed for sixty (60) days or more or a decree or
        order
        granting the relief sought in such case or proceeding shall be entered by
        a
        court of competent jurisdiction;

       

      (v)
        Borrower, without the prior written consent of Lender (A) files a petition
        seeking relief under the Bankruptcy Code, or any other applicable federal,
        state
        or foreign bankruptcy or other similar law, rule or regulation, (B) consents
        to
        or fails to contest in a timely and appropriate manner the institution of
        proceedings thereunder or the filing of any such petition or the appointment
        of
        or taking possession by a custodian, receiver, liquidator, assignee, trustee
        or
        sequestrator (or similar official) for Borrower or for any substantial part
        of
        Borrower’s assets, (C) makes an assignment for the benefit of creditors, (D)
        takes any action in furtherance of any of the foregoing; or (E) admits in
        writing its inability to, or is generally unable to, pay its debts as such
        debts
        become due; 

       

      (vi)
        If
        this Promissory Note, the Security Agreement, or any financing statement,
        document or other instrument executed, delivered or filed in connection herewith
        or with the security interest granted to Lender hereunder, shall, for any
        reason, fail or cease to create a valid and perfected lien on or security
        interest in any or all of the Collateral or the Collateral shall be compromised,
        encumbered or, in the case of the common stock, invalid, cancelled or otherwise
        rescinded;

       


      
        
           

          


          
          

        

        
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      (vi)
        If
        Borrower shall default on any material obligations of Borrower or an event
        of
        default shall occur with respect to any material agreement of Borrower, whether
        such agreement shall be in effect or effective subsequent to this Promissory
        Note.

       

      (b)
        Immediately upon
        the
        occurrence of any Event of Default, all
        of
        the Obligations of Borrower hereunder shall become immediately due and payable
        to Lender and the Obligations shall thereafter accrue interest at the Default
        Rate from the date of any Event of Default until such Obligations are paid
        in
        full (an “Accelleration”). Promptly upon the occurrence of an Acceleration,
        Lender shall send Borrower written notice of the date upon which the
        Acceleration is effective and the names of two (2) representatives of Lender
        (“Lender Nominees”) to be immediately appointed to the Board of Directors of
        Borrower (the “Default Notice”). The Lender Nominees shall be appointed to the
        Board of Directors of Borrower not less than five days following the date
        of the
        Default Notice. Except with respect to an Event of Default under Section
        13(a)(iv) and (v), Borrower shall have forty five (45) days (the forty fifth
        day
        hereinafter being the “Final Payment Date”) from the date of the Default Notice
        to pay Lender the total amount of the Obligations due and owning under this
        Promissory Note. In the event that Borrower shall fail to satisfy in full
        all of
        the outstanding Obligations under this Promissory Note on or before the Final
        Payment Date, then Lender
        may (i) proceed to protect and enforce Lender’s
        rights
        by suit in equity, action at law and/or other appropriate proceeding, either
        for
        specific performance of any covenant or condition contained in this Promissory
        Note, the Security Agreement, or in any instrument or document delivered
        to
        Lender pursuant to this Promissory Note , or in aid of the exercise of any
        power
        granted in this Promissory Note or any such instrument or document, and (ii)
        proceed to enforce payment of the Obligations in such manner as Lender may
        elect,
        including the foreclosure of the Collateral in accordance with the terms
        of the
        Security Agreement,
        and to
        realize upon any and all rights of Lender hereunder. Upon the occurrence
        of any
        Event of Default under Section 13(a)(iv) and (v), Lender shall have a right
        to
        immediately enforce its rights hereunder and proceed against or foreclose
        upon
        the Collateral without regard to the 45 day period set forth in this Section
        13(b) To the extent not prohibited by applicable law which cannot
        be
        waived, all of Lender’s rights hereunder shall be cumulative. Lender shall have
        all other rights and remedies not inconsistent herewith as provided under
        applicable law or in equity, and no exercise by Lender of one right or remedy
        shall be deemed an election, and no waiver by Lender of any Event of Default
        shall be deemed a continuing waiver. No delay by Lender shall constitute
        a
        waiver, election or acquiescence by it.

       

      (c)
        In
        the event that the Obligations hereunder shall be paid in full by or on behalf
        of Borrower, after the Acceleration of this Promissory Note but prior to
        the
        Final Payment Date, then this Promissory Note shall be deemed paid in full,
        Lender shall promptly release any lien of Lender on the Collateral, and each
        Lender Nominee shall immediately resign from the Board of Directors of Borrower.
        

       

      14.
        Certain Rights
        and Waivers.
        To the
        extent not prohibited by the provisions of applicable law, Borrower hereby
        expressly waives: (a) all presentments, demands for performance, notices
        of
        nonperformance (except to the extent required by this Note), protests, notices
        of protest and notices of dishonor; (b) any requirement of diligence or
        promptness on the part of Lender in the enforcement of its rights under this
        Note; (c) any and all notices of every kind and description which may be
        required to be given by any statute or rule of law; and (d) any 

       


      
        
           

          


          
          

        

        
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      defense
        (other than indefeasible payment in full) which it may now or hereafter have
        with respect to its liability under this Note.

       

      15.  Assignments.
        Borrower may not assign or transfer any of its rights or obligations hereunder
        without the express, written consent of Lender. Any such purported assignment
        or
        transfer by Borrower without the express, written consent of Lender shall
        be
        null and void ab
        initio.
        

       

       

      16.  Costs
        and Expenses.
        Borrower agrees to pay all costs and expenses of Lender, including without
        limitation all fees and disbursements of counsel, advisors, consultants,
        examiners and appraisers for Lender, in connection with (a) the issuance
        of this
        Promissory Note and advancement of principal amount hereunder (which fees
        and
        disbursements associated with the origination of this Promissory Note shall
        not
        exceed $3,500.00), (b) any enforcement (whether through negotiations, legal
        process or otherwise) of this Promissory Note, (c) any workout or restructuring
        of this Promissory Note during the pendency of one or more Events of Default,
        (d) any bankruptcy case or proceeding of Borrower or any appeal thereof,
        and (e)
        upon the occurrence and during the continuance of an Event of Default, any
        efforts to verify, protect, evaluate, assess, appraise, collect, sell, liquidate
        or otherwise dispose of any of the Collateral.

       

      17.
        CHOICE OF LAW. THE
        VALIDITY OF THIS NOTE, THE CONSTRUCTION, INTERPRETATION, AND ENFORCEMENT
        HEREOF,
        AND THE RIGHTS OF THE BORROWER AND LENDER WITH RESPECT TO ALL MATTERS ARISING
        HEREUNDER OR RELATED HERETO SHALL BE DETERMINED UNDER, GOVERNED BY, AND
        CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF
        FLORIDA, WITHOUT
        REFERENCE TO CONFLICTS OF LAW PRINCIPLES EXCEPT TO THE EXTENT NECESSARY TO
        ENFORCE THIS CHOICE OF LAW PROVISION.

       

      18.
        Notices.
        All
        communications hereunder shall be in writing and shall be deemed to be duly
        given and received (a) upon delivery if delivered personally or upon confirmed
        transmittal if by facsimile, (b) on the next Business Day if
        sent
        by overnight courier, or (c) four (4) Business Days after mailing if mailed
        by
        prepaid registered mail, return receipt requested, in each case to the
        appropriate notice address or facsimile number. 

       

      19.
        Independent
        Arms Length Transaction.
        It is
        understood and agreed that this Promissory Note, the Security Agreement and
        the
        transactions contemplated hereby and thereby were negotiated in an arms length
        transacton separate and distinct from any other transaction or contractual
        obligations and are independent of any transaction or transactions between
        Borrower, on the one hand, and Lender and any of its affilates or related
        entitles on the other hand. Borrower further agrees that the contractual
        obligations of Borrower hereunder are in no way dependent or conditioned
        upon
        any other agreements, contracts or transactions whatsoever unless expressly
        stated herein. 

       


      
        
           

          


          
          

        

        
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      IN
        WITNESS WHEREOF, the undersigned has executed this Promissory Note as of
        the
        date first written above.

       

      
        	 	
                INVISA,
                  INC.

                 

                By:
                  /s/ Edmund C.
                  King                                   
                  

                Name:
                  Edmund
                  C. King

                Title:
                  Chief
                  Financial Officer

              
	 	 


      

      Signature
        page to Senior Secured Promissory Note, dated February 28,
        2007