Lorell Heavy-duty Standard-height Stack Chairs - Plastic Seat Material - Plastic Back Material - Steel Frame Material - Black - 4 / Carton Heavy-duty chairs stack easily for compact storage. Stack up to 12 chairs. The seat and back are made of an injection-molded plastic for easy-to-clean seating. Waterfall seat front helps promote good blood circulation. Small, convenient slot in the top of the back makes it easy to place and relocate chairs. Frame is made of sturdy, thick steel with a black finish. Weight capacity is 250 lb.