QuickConnect Capture Plates are designed to work with popular king pin box models; simplifying and significantly reducing installation times. Most QuickConnect applications slip over the king pin and are held in place by a set screw and nylon spacer, holding it onto the king pin box. When the trailer is hooked up to the hitch, the Capture Plate's wedge isolates the king pin from turning in the fifth wheel plate, causing the Cam Assembly to activate and allowing the SuperGlide to move as turns are being made. Note: Use Straight edge when measuring to the leading edge of the kingpin box for measurements"B" and "C". CAUTION: Measurement "A" cannot be smaller than noted.