The Rack Mounted Leg Curl and Extensions attachment helps to provide leg strength, balance, and coordination when performing one-leg hamstring curls or seated leg extensions. The attachment features a unique leg roller pad, a square seat pad that adjusts with a turn knob for seated or standing movements, and a quick-mount J-hook style design that easily secures on either P5 Series Power Racks. By mounting to the inside of the power rack, you can utilize the uprights as a stabilizing factor helping with proper form during standing leg curl movements. Reduces the risk in hamstring and knee injuries with the benefit of this versatile plate-loaded rack attachment. Be compatible with racks in 3" ×3“ uprights, 1” hole diameter, like P5 rack Perform standing leg curl movements and seated extensions Fits Olympic sized weight plates Two assembly pins to adjust bottom pad for different heights Weight Capacity: 250LBS