|   | Marketing Services Department    |
|--------|----------------------------------|
|   | Fisher Scientific Company L.L.C. |
|   | 2000 Park Lane                   |
|   | Pittsburgh, PA 15275             |

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|   | Fisher HealthCare            |
|--------|------------------------------|
|   | 9999 Veterans Memorial Drive |
|   | Houston, TX 77038            |
|   | Attn: Clinical Marketing     |
|   |                         |

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| Sincerely, ****    | **ACCEPTED For Fisher:**         |
|--------------------|----------------------------------|
| ** **         | ** **                       |
| ** **         | ** **                       |
| Todd M. DeMatteo   | **____________________________** |
| President/CEO **** | Title:                           |
| ****               | ****                             |
|                    |                             |

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|   | A. DiaSys Corporation (hereinafter      referred to as "Seller"), having its principal office and place of business      at 81 West Main Street, Waterbury, Connecticut 06702 USA, hereby guarantees      that all products (including their packaging, labeling and shipping) comprising      each shipment or other delivery hereinafter made by Seller (hereinafter      referred to as "Products") to at an order of Fisher Scientific Company,      LLC, a limited liability company, having its principal place of business      at 2000 Park Lane, Pittsburgh, Pennsylvania 15275, or to any of its branches,      divisions, subsidiaries, affiliates, or any their customers (hereinafter,      collectively referred to as "Fisher"), are, as of the date of such shipment      or delivery, in compliance with applicable federal, state and local laws,      and any regulations, rules, declarations, interpretations and orders issued      thereunder, including, without limitation, the Federal Food, Drug and Cosmetic      Act, as amended, and conform to representations and warranties made by Seller      in its advertising, product labeling and literature.       B. Further, with respect to any Product that is privately labeled for Fisher,      Seller agrees to make no change in such Products or the Fisher artwork on      the labeling or packaging relating thereto without first obtaining the written      consent of Fisher. Seller recognizes that Fisher is the owner of the trademarks      and trade names containing Fisher which it may elect to use in the promotions      and of such private label Products and that Seller has no right or interest      in such trademarks or trade names. Seller shall periodically analyze and      review packaging and labeling for any Products which are private labeled      for Fisher to ensure conformity with the provisions of paragraph A hereof      and the adequacy of Product warnings and instructions. |   | C. Seller hereby agrees that it      will reimburse Fisher for all reasonable out-of-pocket costs and expenses      incurred in connection with any product corrective action or recall relating      to the Products which is requested by Seller or required by any governmental      entity.       D. Seller agrees to procure and maintain on an occurrence form basic product      liability insurance with respect to the Product and commercial liability      coverings relating to this Guaranty, with insurer(s) having each rating(s)      of A or better, naming Fisher as an additional insured (Broad Farm Vendors      Endorsement), with minimum limits in each case of $2,000,000. Seller shall      promptly furnish to Fisher a certificate of insurance and renewal certificates      of insurance evidencing the foregoing coverages and limits. The insurance      shall not be canceled, reduced or otherwise changed without providing Fisher      with at least ten (10) days prior written notice.       E. Seller agrees to and shall protect, defend, indemnify and hold harmless      Fisher (and with respect to Subparagraph E below, Fisher's customers) from      any and all claims, actions, costs, expenses, and damages, including attorneys'      fees and expenses arising out of (i) any actual or alleged patent, trademark      or copyright infringement in the design, composition, use, sale, advertising      or packaging of the Products; (ii) any breach of this representation or      warrantees set forth in this Guaranty; (iii) the sale or use of the Products      where such liability results from the act or omission of Seller (whether      for breach of warranty, strict liability in tort, negligence or otherwise).            F. Distributor shall indemnify Seller from and against any claims, lawsuits,      losses, liabilities, and damages of any nature arising out of or relating      to any claim caused |   |
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|   | by distributor's gross negligence      or willful acts.       G. Seller agrees to and shall provide to Fisher material Safety data sheets      and other information concerning any Product as required by then applicable      federal, state or local law.       H. Seller agrees to and shall accept, at its facility, all of Fisher's unsold      or expired Products containing hazardous chemicals, materials or substances      for disposal, recycling or use. Fisher shall be responsible for packing      and transportation costs to Seller. Seller shall be responsible for all      other costs, including, without limitation, any costs associated with Seller's      disposal, recycling or use.       I. If the Products to be furnished by Seller are to be used in the performance      of a U.S. Government contract or subcontract, those clauses of the applicable      U.S. Government procurement regulation which are mandatory required by Federal      statute to be included in U.S. Government subcontracts shall be incorporated      herein by reference including, without limitation, the Fair Labor Standards      Act of 1938 as amended.       J. The representations and obligations set forth herein shall be continuing      and shall be binding upon the Seller and his or its heirs, executors, administrators,      successors and/or assigns, whichever the case may be, and shall inure to      the benefit of Fisher, its successors and assigns and to the benefit of      its officers, directors, agents and employees and their heirs, executors,      administrators, and assigns.       K. the agreements and obligations of Seller set forth in this Guaranty are      in consideration of purchases made by Fisher from Seller and said obligations      are in addition to (and supersede to the extent of any conflict) any obligations      of Seller to Fisher or Fisher to Seller. This Guaranty shall be effective      upon the first sale to Fisher of any Product by Seller, and the |   | obligations of Seller under this      Guaranty shall survive and be enforceable in accordance with its terms.            L. Seller represents and warrants that its systems and the Products being      sold hereunder are Year 2000 compliant and that functionality will not be      affected dates prior to, during and after January 1, 2000.       SELLER       DIASYS CORPORATION  Name Under Which Seller's Business is       Conducted  Signature of Authorized Representative  Title                                                          Date            DISTRIBUTOR  Signature of Authorized Representative  Title                                                          Date |   |
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