18 inches wide, 16 inches deep, and 4 inch height. Gray / black. Non-inflatable. High-density foam provides comfort and reduces pressure. Incontinent-proof, wipe-clean vinyl cover. Two-color surfaces act as reminders to reposition patient. Safety ties secure wedge to wheelchair. "Optional firm foundation for elimination of wheelchair hammock effect ". Firm foundation eliminates pressure caused by sling-seats. . WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov