 If A orders 1000 blue coathangers and B ships them out, that shipment is considered to be a conveyance of acceptance of A's offer to buy the coathangers.Defective performance is also an acceptance, unless accompanied by an explanation.For example, if A orders 1000 blue coathangers, and B mistakenly ships 1000 red coathangers, this is still an acceptance of the contract.