AMENDMENT
      NO. 1 TO

     

    SECURED
      CONVERTIBLE DEBENTURE NO. MEP-3

     

    THIS
      AMENDMENT NO. 1 TO SECURED CONVERTIBLE DEBENTURE NO. MEP-3
      (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. MEP-3 dated December 28, 2005 (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 3(c)(i) “Conversion
      Price”.
      Section 3 (c)(i) of the Debenture is hereby amended and replaced in its entirety
      with the following: 

     

    “(i)
      The
      Holder shall be entitled to convert, at its sole option, at any time a portion
      or all amounts of principal and interest due and outstanding under this
      Debenture into shares of the Obligor’s Common Stock at the lesser of (i) $0.04
      (the “Fixed
      Conversion Price”)
      or
      (ii) eighty percent (80%) of the lowest Closing Bid Price of the Common Stock
      during the ten (10) Trading Days immediately preceding the Conversion Date
      as
      quoted by Bloomberg, LP (the “Market
      Conversion Price”).
      The
      Fixed Conversion Price and the Market Conversion Price are collectively referred
      to as the “Conversion
      Price”.
      The
      Conversion Price may be adjusted pursuant to the other terms of this
      Debenture.”

     

    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:  Chief
                Executive Officer and

            
	 	 	
              Chief
                Financial Officer

            
	 	 	 
	 	 	
              BUYER:

            
	 	 	
              MONTGOMERY
                EQUITY PARTNERS, LTD.

            
	 	 	
              By:
                Yorkville Advisors, LLC

            
	
               

            	 	
              Its:
                General Partner

            
	 	 	 
	 	 	
              By: 
                /s/
                Mark Angelo

            
	 	 	
              
                

              

              Name:
                Mark Angelo

            
	 	 	
              Title:
                President and Portfolio Manager

            


    

    


    
      
         

      

      
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