To cancel an order, click on the red "X" located at the outside edge of the order's displayed size marker. If multiple orders are consolidated at that price, all orders at that price will be cancelled.

1. Pressing on the red "X" will cancel all orders consolidated at the corresponding price level

2. Pressing down on the right mouse button with the mouse cursor hovering over the order will display all orders consolidated at that price. You can select any individual order for cancellation.

3. Pressing on the large red "X" will cancel all orders on either the "BUY" side (in this example) or the sell side

You can also cancel "ALL" orders via the right mouse click context menu.