The Commercial Custom Rules in International Trade, Interaction between CISG & Incoterms Rules

United Nations Convention on the International Sale of Goods provide as default rules. Article 6 of convention gives right to change or dismiss the convention rule to the parties. Consequently, the parties can perform articles 66-70 of convention in several kinds, they can exclude perform some rules, or exclude their effects, in this situation party express their agreement. They can perform their agreement in regard to article 6 of convention, but the question is: where this amendment result is excluding all convention rules about risk, or exclude some rules effects?
When Party agreements amendment convention rule, they can agree that international custom (so incoterms rules) perform. The next problem is: if the party doesn’t expressly agreed about performance of incoterms rules; is it Possible to perform it as part of party’s contracts? In this article we consider the effects of party about substituting convention rule with incoterms rule and at the end clear that courts know incoterms as parts of agreement when party express or don’t express it.