Drive Medical 8040-5 Gel-U-Seat Lite General Use Gel Cushion with Stretch Cover, 18" x 18" x 2". The Gel-U-Seat Lite cushion from Drive and Mason Medical is specifically designed to redistribute pressure to assist in the prevention of pressure ulcers while providing patient comfort by incorporating high-density foam surrounding a dual-chamber gel bladder. The fluid-resistant, low-shear stretch cover includes tie straps to secure to wheelchair.