A contract of sale of goods containing words identifying its subject matter, e.g. 1000 tonnes of Western White Wheat. Even when the subject matter of the contract is physically ascertained at the time of contracting, e.g. a particular motor car, the contract may contain words of description or identification. The goods delivered must match their description in the contract; otherwise the seller is in breach of an implied condition of the contract and the buyer, if he acts promptly, may reject the goods.