Primary Peg

What is price pegging (Peg) and the "Primary" mode

A peg order sets the price for you: the exchange keeps it at the right spot in the order book and moves it along with the market — you don't enter the price by hand. The "Primary" mode pegs the price to YOUR own side of the book: when buying, the price stays at the best buy price (bid); when selling, at the best sell price (ask). This keeps your order at the edge of its own queue, without crossing the market.