Lock-in refers to an operation mode in which investors lock the current profit and loss level and position size by establishing long and short positions at the same time for the purpose of risk control in futures trading. Because the profits and losses of bulls and bears offset each other, the impact of market fluctuations on investors can be reduced. For example, if an investor establishes both long and short positions in futures options, if the market fluctuates greatly, the long position will lose money and the short position will make a profit; If the market fluctuation is small, the profit and loss of the two positions are basically offset.

Locking usually requires a stable market environment and a high level of technology and risk awareness. Investors need to be clear about their profits and losses, make timely decisions and correct their locking strategies. When the market falls, investors need to close their positions as soon as possible to make a profit; When the market rises, investors need to close their positions as soon as possible to avoid increasing losses. In addition, investors need to pay close attention to market prospects and risk factors, and adjust their locking ratio and position size.

Although locking operation can effectively reduce the transaction risk, it also has certain limitations and application scenarios. For example, in the case of large market fluctuations, the profit and loss of long and short positions may be greatly deviated, reducing the locking effect. At the same time, the lock-in operation needs to consider factors such as transaction cost and margin adjustment, which requires higher funds for investors. Therefore, investors need to make reasonable judgments and treatments according to their own investment experience and market conditions when locking positions.