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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then, in addition to any other remedies it might have under this Agreement or by law, Vapotherm may cancel that purchase order or the portion thereof relating to those cartridges, as applicable. 3.7 Invoices and Payment Terms. On delivery by Medica of a shipment of Cartridges in accordance with Section 3.3, Medica shall issue to Vapotherm an invoice for that shipment stating a price consistent with the terms of this Agreement. Vapotherm shall pay each such invoice in full within [* * *] Calendar Days from the date of invoice, unless Vapotherm has rejected the shipment in question in accordance with Section 4.2. -3- [* * *] = Certain confidential information contained in this document, marked by brackets, has been omitted and filed separately with the Securities and Exchange Commission pursuant to Rule 406 of the Securities Act of 1933, as amended. 3.8 Delay in Payment. Upon delay of payment beyond [* * *] days from invoice date, Medica at its' sole discretion may levy an increase to the net transfer price a [* * *]% per week to a maximum of [* * *]%. ARTICLE 4 QUALITY OF THE CARTRIDGE 4.1 Conformity with Specifications. Any Cartridges that Medica manufactures under this Agreement must conform to the specifications in Exhibit D (the "Specifications") and (2) be manufactured, labeled, packaged, stored, and tested (while in the possession of, stored by, or under the control of Medica) in accordance with cGMP. Medica shall provide adequate packaging for protection during normal shipping and handling environments. 4.2 Conditions to Rejection. In order to be entitled to reject any Cartridge, Vapotherm must notify Medica of any failure of the Cartridge to meet the Specifications or otherwise comply with this Agreement. Misuse or improper storage will not be grounds for rejection. 4.3 Rejection. Vapotherm may reject any Cartridge that does not meet the Specifications or otherwise comply with this Agreement (any such Cartridge, a "Nonconforming Cartridge"). If Medica accepts that Vapotherm was entitled to reject the Nonconforming Cartridge(s) and Vapotherm has already paid the purchase price for the Nonconforming Cartridge(s), then, within [* * *] Calendar Days after receiving notice from Vapotherm under Section 4.2, Medica shall, at Vapotherm's election, either replace the Nonconforming Cartridge(s) at no additional cost to Vapotherm or reimburse Vapotherm for the purchase price of the Nonconforming Cartridge(s) via wire transfer. Further, if Medica accepts that Vapotherm was entitled to reject the Nonconforming Cartridge(s) and Vapotherm has not already paid the purchase price for the Nonconforming Cartridge(s), then, within [* * *] Calendar Days after receiving notice from Vapotherm under Section 4.2, Medical shall, at Vapotherm's election, either replace the Nonconforming Cartridge(s) at no additional to Vapotherm beyond the original purchase price charged to Vapotherm for the Nonconforming Cartridge(s) or cancel that purchase order or the portion thereof relating to the Nonconforming Cartridge(s), s applicable. (b) If Medica does not agree that one or more Cartridges constitute Nonconforming Cartridges, the Joint Review Committee, consisting of quality assurance representatives from both companies, must consider the matter. If after consideration by the Joint Review Committee the parties are unable to reach agreement within [* * *] Calendar Days after the date Medica received notice from Vapotherm under Section 4.2, they shall submit the dispute to arbitration in accordance with Section 14.5. -4- [* * *] = Certain confidential information contained in this document, marked by brackets, has been omitted and filed separately with the Securities and Exchange Commission pursuant to Rule 406 of the Securities Act of 1933, as amended. 4.4 Nonconformity Default Rights. If for any reason other than an event of Force Majeure Medica (1) fails to replace any Nonconforming Cartridge as required by Section 4.3 or (2) fails to replace any Nonconforming Cartridge within [* * *] Business Days after a dispute regarding whether any rejected quantity of Cartridge constitutes Nonconforming Cartridge is decided in Vapotherm's favor, then, in addition to any other remedies it might have under this Agreement or by law, Vapotherm may cancel that purchase order or the portion thereof of relating to the Nonconforming Cartridge, as applicable. 4.5 Acceptance of Cartridges. If Vapotherm does not notify Medica that one or more Cartridges do not meet the Specifications or otherwise fail to comply with this Agreement, those Cartridges will be deemed to have been accepted by Vapotherm as being fully compliant with the Specifications and this Agreement. 4.6 Quality Monitoring. Medica will periodically sample and trend the Cartridge performance in accordance with specification and Medica's internal production tests
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Extract the exact clause related to "Warranty Duration" from the excerpt above.