Heading Caring for you. Purpose Coccyx Cushion Manufacturer Apex Med Uses Premium quality self molding memory foam helps reduce back pain. Ergonomic design reduces pressure on the tailbone and spine. Helps restore natural lumbar curve by tilting pelvis forward. Convenient transport strap. Hypo-allergenic. Removable washable cover. Fits most standard wheelchair and transport chair seats. 3 inches high x 18 inches wide x 16 inches deep.