Specifications Upholstery Frame: reinforced hardwood and plywood. Seat: (20/910-20/913-74) loose cushion of polydacron. Deck: (20/910-20/913-74) high density polyurethane over resilient webbing. Seat: (20/915-20/918-74) tight seat of polydacron over resilient webbing. Back: tight back of polydacron over polypropylene webbing. Arms: polyurethane over hardwood.