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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4.3 Transfers. This Warrant and the Shares issuable upon exercise of this Warrant (and the securities issuable, directly or indirectly, upon conversion of the Shares, if any) may not be transferred or assigned in whole or in part without compliance with applicable federal and state securities laws by the transferor and the transferee (including, without limitation, the delivery of investment representation letters and legal opinions reasonably satisfactory to the Company, as reasonably requested by the Company). After compliance with all restrictions on transfer set forth in this Section 4.3, and within a reasonable time after the Company's receipt of an executed assignment agreement, the transfer shall be recorded on the books of the Company upon the surrender of this Warrant, properly endorsed, to the Company at its principal offices, and the payment to the Company of all transfer taxes and other governmental charges imposed on such transfer. In the event of a partial transfer, the Company shall issue to the new holders one or more appropriate new warrants. 4.4 Notices. All notices and other communications from the Company to the Holder, or vice versa, shall be deemed delivered and effective when given personally or mailed by first-class registered or certified mail, postage prepaid, at such address as may have been furnished to the Company or the Holder, as the case may (or on the first business day after transmission by facsimile) be, in writing by the Company or such Holder from time to time. Effective upon receipt of the fully executed Warrant, all notices to the Holder shall be addressed as set forth on the signature page hereto until the Company receives notice of a change of address in connection with a transfer or otherwise. Notice to the Company shall be addressed as set forth on the signature page hereto until the Holder receives notice of a change in address. 4.5 Waiver. This Warrant and any term hereof may be changed, waived, discharged or terminated only by an instrument in writing signed by the party against which enforcement of such change, waiver, discharge or termination is sought. 4.6 Counterparts. This Warrant may be executed in counterparts, all of which together shall constitute one and the same agreement. 4.7 Governing Law. This Warrant shall be governed by and construed in accordance with the laws of the State of New York, without giving effect to its principles regarding conflicts of law. Please indicate your acceptance of these terms by countersigning where indicated below. Slinger Bag Inc. Name: Title: Agreed and accepted: Aitan Zacharin 14 Appendix 1 SLINGER BAG INC. EXERCISE NOTICE Reference is made to the Warrant Agreement dated 30 April 2020 between Slinger Bag Inc. (the "Company") and Aitan Zacharin (the "Warrant Agreement"). In accordance with and pursuant to the Warrant Agreement, the undersigned hereby elects to exercise the Warrant to purchase shares of common stock of the Company as set forth below. Capitalized terms used but not defined herein have the meanings assigned to such terms in the Warrant Agreement. Date of Exercise: __________________________________________________ Number of shares of ordinary/common (or its equivalent) stock to be purchased:________________________________ Please issue shares of common stock in the following name and to the following address: Issue to: _________________________________________ Address: _________________________________________ Telephone Number: ________________________________ Email address: _________________________________ Holder: __________________________________________ By: Title:
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Extract the exact clause related to "Warranty Duration" from the excerpt above.

assistant: Not found.