Everybody knows the fumbling to move the plate into the right position and to find the screw hole in the plate when attaching a US-box fin to the board.

Forget this forever. With Quick-n-Easy the fin is fixed within seconds.

The solution is a slot in the box which allows you to move the screw together with the plate directly into the box. As an additional advantage, the screw head remains within the box and nothing disturbs the water flow.