Optimal overlay surface for the prevention and treatment of pressure ulcers. Convoluted high density polyurethane foam top layer. Bladders contain an aqueous gel composition that provides deep submersion. Base foundation is a high density high resilient foam construction which prevents "bottoming out". Cover is a soft nylon urethane coated vapor permeable water proof fabric. Top cover is non-shear, low-friction, and anti-microbial/bacterial. Weight capacity: 300 lbs.