system: You are a contract-analysis assistant performing a span-extraction task. You are given an excerpt from a commercial contract and the name of a clause type to locate within it.

Return the exact text of the requested clause, copied verbatim from the excerpt — identical wording and punctuation, with no paraphrasing, summarising, explanation, or added commentary.

The excerpt is one window of a much longer contract and often will not contain the requested clause. If the requested clause does not appear in this excerpt, respond with exactly: Not found.

Output only the extracted clause text, or the exact string `Not found.` — nothing else.

user: Contract excerpt:
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by Diplomat for KI, Inc.'s prior approval before any product is distributed or sold, and at the latest within thirty (30) days after the date first written above. Any proposed change in certificates of insurance shall be submitted to KI, Inc. for its prior approval. KI, Inc. shall be entitled to a copy of the then prevailing certificate of insurance, which shall be furnished KI, Inc. by Diplomat. As used in the first 2 sentences of this paragraph 6, "KI, Inc." shall also include the officers, directors, agents, and employees of the KI, Inc., or any of its subsidiaries or affiliates. 9. Quality of Merchandise. Diplomat agrees that the products covered by this Agreement shall be of such style, appearance and quality as to be adequate and suited to their exploitation to the best advantage, protection and enhancement of KI's name and the good will pertaining to such name. Diplomat further agrees that (a) such products will be manufactured, sold and distributed in accordance with all applicable Federal, State and local laws, (b) that the policy of sale, distribution, and/or exploitation by Diplomat shall be to the best advantage of KI, Inc. and KI, and (c) that the latter policy shall in no manner reflect adversely upon the good name of KI and KI, Inc. To this end, Diplomat shall, before selling or distributing any of the products, furnish to KI, Inc. for its approval, free of cost, a reasonable number of samples of each product and the cartons, containers, packing and wrapping material for such products. The quality and style of such products, as well as of any carton, container or packing or wrapping material, shall be subject to the approval of KI, Inc., which shall not be unreasonably withheld or delayed. Failure to reject any product, carton, container, or packing or wrapping within 15 days of receipt of such item or items by KI, Inc. shall be deemed an acceptance of the quality and style of such item or items. After samples have been approved pursuant to this paragraph, Diplomat shall not depart therefrom in any material respect without KI, Inc.'s prior written consent. From time to time after Diplomat has commenced selling the products, and upon KI, Inc.'s written request, Diplomat shall furnish without cost to KI, Inc. not more than ten (10) additional random samples of each product being manufactured and sold by Diplomat under this Agreement, together with any containers and packing and wrapping material used in connection with such products. 6 10. Labeling. (a) Diplomat agrees that it will cause to appear on or within each product sold by it under this license and on or within all advertising, promotional, or display material bearing KI's name (i) the notice "Copyright (c) (year) ______" and any other notice desired by KI, Inc and (ii) where such product, advertising, promotional, or display material bears a trademark or service mark, appropriate statutory notice of registration or application for registration thereof. In the event that any product is marketed in a carton, container, packing or wrapping material bearing KI's name, such notice shall also appear upon the said carton, container, packing or wrapping material. Each and every tag, label, imprint, or other device containing any such notice and all advertising, promotional or display material bearing KI's name shall be submitted by Diplomat to KI, Inc. for its written approval prior to use by Diplomat. Approval by KI, Inc. shall not constitute waiver of KI, Inc.'s rights or Diplomat's duties under any provision of this Agreement. (b) Diplomat agrees to cooperate fully and in good faith with KI, Inc., at the expense of KI, Inc., for the purpose of securing and preserving KI, Inc.'s (or any grantor of KI, Inc.'s) rights in and to KI's name. It is agreed that nothing contained in this Agreement shall be construed as an assignment or grant to Diplomat of any right, title or interest in or to KI's name, it being understood that all rights relating thereto are reserved by KI, Inc., except for the license hereunder to Diplomat of the right to use and utilize KI's name only as specifically and expressly provided in this Agreement. Diplomat hereby agrees that at the termination or expiration of this Agreement Diplomat will be deemed to have assigned, transferred and conveyed to KI, Inc. any trade rights, equities, good will, titles or other rights in and to KI's name which may have been obtained by Diplomat or which may have vested in Diplomat in
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Extract the exact clause related to "Warranty Duration" from the excerpt above.