Section 2311 - Options and cooperation respecting performance(a) Specifying particulars of performance.--An agreement for sale which is otherwise sufficiently definite (section 2204(c)) to be a contract is not made invalid by the fact that it leaves particulars of performance to be specified by one of the parties. Any such specification must be made in good faith and within limits set by commercial reasonableness.(b) Specifying assortment of goods and shipping arrangements.--Unless otherwise agreed specifications relating to assortment of the goods are at the option of the buyer and except as otherwise provided in section 2319(a)(3) and (c) (relating to F.O.B. and F.A.S. terms) specifications or arrangements relating to shipment are at the option of the seller.(c) Remedies for failure to specify or cooperate.--Where such specification would materially affect the performance of the other party but is not seasonably made or where the cooperation of one party is necessary to the agreed performance of the other but is not seasonably forthcoming, the other party in addition to all other remedies:(1) is excused for any resulting delay in his own performance; and(2) may also either proceed to perform in any reasonable manner or after the time for a material part of his own performance treat the failure to specify or to cooperate as a breach by failure to deliver or accept the goods. 1979, Nov. 1, P.L. 255, No. 86, § 1, effective 1/1/1980.