AMENDMENT
      NO. 1 TO

     

    SECURED
      CONVERTIBLE DEBENTURE NO. TCHL-1-1

     

    THIS
      AMENDMENT NO. 1 TO SECURED CONVERTIBLE DEBENTURE NO.
      TCHL-1-1
      (this
“Amendment”),
      is
      entered into by and between TECH
      LABORATORIES, INC. a
      New
      Jersey corporation (the “Company”),
      and
      the undersigned Buyer (the “Buyer”).

     

    WHEREAS:

     

    A. The
      Company hereto previously issued to the Buyer that certain Secured Convertible
      Debenture No. TCHL-1-1 dated April 20, 2007 (the "Debenture").

     

    B. The
      parties to the Debenture now desire to amend certain provisions set forth in
      the
      Agreement as more fully described herein.

     

    NOW,
      THEREFORE,
      in
      consideration of the premises and the mutual covenants contained herein and
      other good and valuable consideration, the receipt and sufficiency of which
      are
      hereby acknowledged, the Company and the Buyer hereby agree as
      follows:

     

    1. AMENDMENT
      OF SECTION 4(a)(ii) “Conversion
      Price”.
      Section
      4 (a)(ii) of the Debenture is hereby amended and replaced in its entirety with
      the following: 

     

    “(ii)
      “Conversion
      Price”
means,
      as of any Conversion Date the lesser of (a) $0.04 (the “Fixed
      Conversion Price”),
      subject to adjustment as provided herein, or (b) eighty percent (80%) of the
      lowest Closing Bid Price of the Company’s Common Stock during the ten (10)
      Trading Days immediately preceding the Conversion Date (the “Market
      Conversion Price”).

     

    2. EFFECT
      ON OTHER TERMS.
      This
      Amendment shall be deemed effective as of May 31, 2007. All other terms set
      forth in the Debenture shall remain unchanged and this Amendment, and the
      Debenture shall be deemed a single integrated agreement for all
      purposes.

     

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    IN
      WITNESS WHEREOF,
      the
      parties have caused this Amendment to the Debenture to be duly executed as
      of
      day and year first above written.

     

    
      	 	 	 
	 	
              COMPANY:

              
                TECH
                  LABORATORIES, INC.

              

            
	 
 	 
 	 
 
	
            	By:  	/s/ 
John
              King
	 	
              

              Name:
                John King

              
                Title: 
                  Director and Chief Executive
                  Officer

              

            


    

     

    
      	 	 	 
	 	
              BUYER:

              
                CORNELL
                  CAPITAL PARTNERS, L.P.

              

            
	 
 	 
 	 
 
	 	By:  	 Yorkville
              Advisors, LLC
	 	Its:
              	 General Partner


    

     

    
      	 	 	 
	
            	By:  	/s/
              Mark Angelo
	 	
              

              
                Name:
                  Mark Angelo

              

              Title:
                President and Portfolio Manager

            
	 	 


    

     

    
      
         

      

      
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