§12A-2-202.

§12A-2-202.
   
   Terms with respect to which the confirmatory memoranda of the parties
   agree or which are otherwise set forth in a writing intended by the
   parties as a final expression of their agreement with respect to such
   terms as are included therein may not be contradicted by evidence of
   any prior agreement or of a contemporaneous oral agreement but may be
   explained or supplemented
   
   (a) by course of dealing or usage of trade (Section 1-205) or by
   course of performance (Section 2-208); and
   
   (b) by evidence of consistent additional terms unless the court finds
   the writing to have been intended also as a complete and exclusive
   statement of the terms of the agreement.