A Crotch Strap Completes a Back Plate System A good crotch strap can really lock in a back plate or any bouyancy compensator system, securing the rig so that it almost becomes a part of your body, virtually eliminating shifting no matter what position you are in the water. On the surface it lifts the diver above the surface by preventing the BC from ridding up when inflated. The X-TEK crotch strap is 2in/50mm wide and attaches to all back plates. It comes with two big stainless steel D-rings that provide excellent clip-on points for gear. It\'s the perfect finishing touch to a successful BC system.