Usage of Trade
A custom within the industry and custom binds all of those who should know about it (sometimes even binding consumers)
Course of dealings
Course of Performance
Means what parties do in performing this one particular contract & creates it’s own history/expectations
Hierachy of terms
1) Express terms (exception - this can be waived via course of performance)
2) Course of performance
3) Course of dealing
4) Usage of trade
Good Faith