The Quick Detach Post or QD P is the family's most straightforward and toolless post. The QDP attaches to any flush cup, whether it is on your rifle, camera cage, or any other piece of kit you may want to connect to your backpack. Insert into the flush cup hole, depress the brass ball on the front with your thumb, and push. To remove, place the post between your forefingers, depress the brass ball, and pull out.