There is no difference between long and short futures. If futures are delivered, there may be unequal delivery grades. If the futures standard is level 2, if the seller holds level 1, then the buyer needs to keep the price difference, which is the premium in futures. If the seller's price is level 3, the seller needs to return the difference to the buyer, which is the falling water in futures. I'm from the futures company. You can ask me any questions.