The Prism Elite Cushion is a seat cushion with a contoured base for individuals with low back pain, arthritis, pressure sores, spinal cord injury and circulatory, lower extremity or mobility disabilities, including people who use wheelchairs or mobility scooters. It is designed for users that require moderate postural support and offers contours that are intended to promote correct seating posture. The Elite Cushion has three distinct layers: a top layer of soft poly foam; a central layer of pressure-relieving viscoelastic foam; and a base layer of contoured, high-density polyurethane support foam to provide positioning. The cover, which has a non-slip bottom, is washable and intended for use with people who may be incontinent. DIMENSIONS: (WxD) (16, 17, 18 or 20) x (16, 18 or 20) inches. The height is 4 inches on the sides and 3 inches on the rear edge. CAPACITY: 250 pounds. WEIGHT: 2.5 pounds. WARRANTY: Two year limited warranty on cushion; 90-day warranty on the cover.