The letter and commitment are economically a written commitment that, in order to impose a deal on his sustainability, is committed and placed on the other hand, so that if he does not fulfill his obligations, he will receive crimes. Due to the volatility of prices globally and other causes, there are usually more common guarantees in foreign trade. A- the price registration guarantee. (b) A good guarantee of work. This is the guarantee of two types. A- is conditional, according to exceptional circumstances. (b) It is unconditioned, that is, there is no ordinary condition contract.