Provides proper positioning and patient comfort. Stretch nylon cover is comfortable, breathable and fluid resistant. 1 year warranty. Helps in the prevention and treatment of pressure sores. High density, high resilient polyurethane foam provides excellent pressure redistribution. Cut-out design removes all pressure on the coccyx bone. Stretch nylon cover is comfortable, breathable and fluid resistant. Safety buckles keeps the cushion in place. Weight Capacity: 250 lbs. (16″, 18″, 20″); +500 lbs. (22″, 24″, 26″, 28″, 30″)