other changes, initiated by Manufacturer, that would impact either Product Costs or process changes at Subcontractor will be implemented at an agreed upon time. Manufacturer will be responsible for their proportionate share of any Product Cost reduction that is a result of engineering investment by the Subcontractor. If the Manufacturer does not pay its proportionate share, the Manufacturer will pay the Product Cost as if the cost reduction had not been made (i.e., the Product Cost prior to the cost reduction as if the cost reduction were not made). The Subcontractor will list the new Product Cost and a line item for engineering investment that accounts for the difference. 3.5 Royalties. In addition to paying the Product Costs of Manufacturer's Products, Manufacturer shall also pay to Subcontractor the following royalty payments (each a "Royalty" and collectively the "Royalties") for each of Manufacturer's Product purchased under this Agreement. Royalties shall be paid 50% at time of shipping and the remaining balance of 50% due in 15-days after the Manufacturer's Products have shipped from the manufacturing facility. a) Non-Rechargeable Products. For Manufacturer's Products that are non-rechargeable, Manufacturer shall pay Subcontractor a Royalty equal to the higher of (i) eighty percent (80.0%) of the Product Cost; and (ii) $80 per unit. b) Rechargeable Products. For Manufacturer's Products that are rechargeable, Manufacturer shall pay Subcontractor a Royalty equal to the higher of (i) one hundred percent (100.0%) of the Product Cost; and (ii) $100 per unit. 3.6 Zounds' Products and Manufacturers Products Built to Manufacturer's Specifications. Subject to Section 7 below, Subcontractor agrees to manufacture Manufacturer's Products (i) that are identical to Zounds' Products allowing Manufacturer to utilize Subcontractor's existing product designs and features and/ or (ii) to specifications provided by Manufacturer from time to time with approval of such changes by Subcontractor. Any