B means active buying, and the transaction is made at the selling price, which is called the external market. Generally, the bullish sign is red.

S stands for active selling, and the transaction is made at the purchase price, which is called internal selling. Generally, the bearish sign is green.

The current quantity is 20 1B, indicating the current active purchase, and the selling price is 20 1 lot.

The current quantity is 35 1S, which means that it is actively sold at present, and it is sold at the purchase price of 35 1 lot.