There are roughly four hedging trading mechanisms in the futures market. The premise of this hedging transaction is that there is some correlation between different futures products, for example, the two commodities are upstream and downstream products, or they can replace each other. Although the varieties are different, they reflect the identity of market supply and demand. Under this premise, buy a futures product, sell another futures product, and then close the position or deliver at the same time to complete the hedging transaction, which is called cross-product arbitrage for short.