Manta Ray - Weightlifting Squat Stabilizer 1. Our patented load distribution device for the back squat exercise. Made from a hi-tech polyurethane polymer, it is virtually indestructible. 2. Instead of the force concentrating in one small area, the Manta Ray increases the surface area by more than 1600% finally making it possible to focus on the movement. 3. The front projections help keep the bar from trying to roll off your back. This allows most people use a more erect posture because it stops the bodies tendency to bend the lifter forward in an attempt to take the stress off the shoulders.