D 1 D2 D3 refers to the rule that futures have three consecutive price limits, and the first trading day and the second trading day are flat. In other words, if your position goes up and down three times in a row, no matter whether you make money or lose money, the exchange will forcibly close the position. The price of each variety in futures is different, and most of them are 4% price limit. Details of each variety can be queried in the software. In addition, if the futures variety D 1 appears the price limit phenomenon, the price limit range of D2 trading day will expand, generally 2 percentage points, and the corresponding margin will also increase.

For example, the normal market price of rebar fluctuates by 4%, but it fluctuates by 6% in D2 trading day and 8% in D3 trading day today.