definiens: shall mean the amount actually received by Purchaser for the sale of the products of the Custom Division to the 30 Customers, less to the extent paid, allowed or given ( a ) any sales or value added tax, ( b ) custom duties and fees, ( c ) freight allowed, ( d ) allowances for lost or damaged merchandise, and ( e ) returns and such discounts or rebates as may have been granted on account of quantity purchase ( but not discounts granted for promptness of payment ) ; provided, that on no account shall separately billed shipping and insurance costs be deemed included in the Net Sales of any product of the Custom Division ; ( 2 ) shall mean any of the twelve month periods, the first of which begins on the first day of the first complete calendar month after Closing and each subsequent one of which begins on an anniversary of such date ; and ( 3 ) shall mean any day on which the commercial banks are generally open for business in the State of Texas ; and ( B ) 8.5 % of the Net Sales in excess of $ 6,600,000 recorded by Purchaser in each Contract Year to the 30 Customers