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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1 EXHIBIT 10.13 EXECUTION COPY ENDORSEMENT AGREEMENT --------------------- This Endorsement Agreement ("Agreement") is made this 13th day of October, 1999 by and between SQUARE TWO GOLF INC., a New Jersey corporation (the "Company"), and KATHY WHITWORTH, an individual, with an address at 302 La Mancha Court, Santa Fe, New Mexico, 87501 (the "Professional"). RECITALS -------- WHEREAS, the Company manufactures and sells women's golf clubs and other golf equipment; WHEREAS, the Professional is a retired Ladies Professional Golf Association ("LPGA") Tour Professional; WHEREAS, the Company desires to utilize the services of the Professional in connection with the promotion, marketing, and sale of a signature line of women's golf clubs and the Company's other products and services; and WHEREAS, the Company and the Professional desire to enter into an agreement pursuant to which the Professional will serve the Company as an independent contractor, on the terms and subject to the conditions set forth herein. NOW, THEREFORE, in consideration of the mutual covenants and agreements contained herein, the Company and the Professional hereby agree as follows: 1. TERM. 1.1 The term of this Agreement shall begin on January 1, 2000 and continue for an initial period of five (5) years unless earlier terminated in accordance with Section 7 hereof, and may be renewed under Section 8 hereof (the initial period plus any renewal period, the "Term"). 2. ENDORSEMENT SERVICES. During the Term, the Professional will provide the services described in this Section 2 (the "Services"): 2.1 The Professional hereby grants to the Company an exclusive license to use her name, likeness, image and personal identification, singly or in any combination, in connection with the production, use, marketing and sale of a "Kathy Whitworth" signature line of women's golf clubs (the "Products"), as described more fully in Section 3 below. 2 EXECUTION COPY 2.2 The Professional agrees to serve as a professional golf instructor during up to ten (10) golf clinics hosted by the Company per calendar year at locations within the United States to be determined by the Company. The golf clinics shall be one or two day events. 2.3 The Professional agrees to serve as a spokesperson for the Company at up to two (2) Professional Golf Association merchandise shows, including but not limited to the PGA Merchandise Shows. 2.4 The Professional hereby grants to the Company the exclusive and worldwide right to use her name, likeness, image and personal identification, singly or in any combination, during the Term and for a period of six (6) months after the Term as provided in Section 2.8, in the creation of two (2) print advertisements per year and one (1) television advertisement per year (together, the "Advertisements") for any golf equipment, along with all rights in any images, videos, advertisement copy or other materials created by the Professional or others. The Professional agrees that the Company shall own all such materials and all intellectual property rights&bbsp;therein for use in perpetuity in any media now known or hereafter devised or developed, including but not limited to the internet. The Professional hereby grants to the Company the worldwide right during the Term and for a period of six (6) months after the Term as provided in Section 2.8 to use, reproduce, print, publish, distribute, broadcast, modify, edit, condense, or expand any materials containing her name, image, likeness or personal identification that are created hereunder. 2.5 The Professional hereby grants to the Company an exclusive license to use her name, likeness, image and personal identification in the Company's catalog of products. 2.6 The Professional agrees to participate in a minimum of five (5) other events per calendar year to market and promote the Company's products, including but not limited to market consultations, each of which shall include meeting with the Company executives to assist in the design, development, marketing and promotion of the Company's products. 2.7 The Professional agrees to use only the golf clubs and golf bags of the Company in any golf event, whether professional or social, during the Term. The Professional agrees (i) to use no golf bag bearing any identification of a competitor of the Company and (ii) to wear no apparel bearing any identification of a competitor of the Company, and will prohibit any caddy of hers from bearing any such identification. 2.8 The Company shall cease use of the name, likeness, image or personal identification of the Professional upon expiration or termination of this Agreement. However, the Company will have the right to dispose of its inventory of Products existing at
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Extract the exact clause related to "Warranty Duration" from the excerpt above.