400.1-205. (1) A course of dealing is a sequence ofprevious conduct between the parties to a particular transactionwhich is fairly to be regarded as establishing a common basis ofunderstanding for interpreting their expressions and otherconduct.
(2) A usage of trade is any practice or method of dealinghaving such regularity of observance in a place, vocation ortrade as to justify an expectation that it will be observed withrespect to the transaction in question. The existence and scopeof such a usage are to be proved as facts. If it is establishedthat such a usage is embodied in a written trade code or similarwriting the interpretation of the writing is for the court.
(3) A course of dealing between parties and any usage oftrade in the vocation or trade in which they are engaged or ofwhich they are or should be aware give particular meaning to andsupplement or qualify terms of an agreement.
(4) The express terms of an agreement and an applicablecourse of dealing or usage of trade shall be construed whereverreasonable as consistent with each other; but when suchconstruction is unreasonable express terms control both course ofdealing and usage of trade and course of dealing controls usageof trade.
(5) An applicable usage of trade in the place where any partof performance is to occur shall be used in interpreting theagreement as to that part of the performance.
(6) Evidence of a relevant usage of trade offered by oneparty is not admissible unless and until he has given the otherparty such notice as the court finds sufficient to prevent unfairsurprise to the latter.
(L. 1963 p. 503 ยง 1-205)