Istisnah is also a sale where a commodity is transacted before it comes into existence. It means to order a manufacturer to manufacture a specific commodity for the purchaser. If the manufacturer undertakes to manufacture the goods for him with material from the manufacturer, the transaction of istisna' comes into existence. It is necessary for Istasnah that the price is fixed and that necessary specification of the commodity to be manufactured are fully agreed between the purchaser and manufacturer. The contract cannot be cancelled unilaterally.