The lock function only exists in investments that can be traded in two directions, and is usually used to hedge open positions. If you don't click the lock order to hedge, you can directly place a reverse order in the same currency group on the opened position, which will result in a relative write-off with the original position. For example, if you open another USD/EUR sell position, the related position will be automatically reversed.

1. Strictly speaking, a lock list refers to warehouse receipts with the same price and the same number of lots in different directions, but in practice, few people do this unless a novice places a wrong order.

2. In order to prevent the huge fluctuation of the opening of the next day, the general lock list finds a reasonable price locking risk before the closing of the first day and unlocks it according to the opening situation of the next day. This method is generally a large capital operation.

Example: February 1, the market was bullish, and the price rose to 2550 before the afternoon closing. It is expected that the price will rise again the next day, so I decided to hold a position overnight, but I was worried that the CBOT market would plummet at night, which would affect the trend of the next day, so I made a selling position at 2550 and locked in a profit of 50 points. If CBOT rises at night and opens the next day, I will close my position and sell it.