Designed For Long Term Users Of Wheelchairs * Provides Comfort For An Entire Seat Or Chair With Soft Comfortable Covoluted Foam And Ties To Secure It * Seat Size Is 18 W X 16 D X 4 H Back Size Is 18 16 X 3 * Helps Promote Good Posture While Cushioning The Body Preventing Sores And Offering A Slip Free Seat