The unit of each lot is the unit standard of the goods in the contract. If it is soybean meal, soybean oil, cotton and other commodities, the spot is generally bought and sold by weight, and futures also agree to take weight as the unit, while some finished products, such as plywood and fiberboard, are stocked by sheets, so they are sold by sheets. The minimum trading volume is lots, and each lot corresponds to a different multiplier. Take corn as an example, the first price is 10 ton. If the unit price of one ton is 2500 yuan/ton, then the value of the first-class contract is 25000 yuan. If the futures charge 10%, it only needs 2500 yuan. If there are 500 pieces of plywood in one hand, if each piece is 120 yuan, the value of the first hand is 60,000 yuan, and if the deposit of 10% is charged, the first hand transaction needs 6,000 yuan.