Steel MAXIMUM COMFORT: Set of 4 commercial extra wide, comfortably contoured, big and tall indoor/outdoor plastic folding chairs for home or business use DURABLE SUPPORT: Double support braces with reinforced 18 gauge steel frame and high impact, stain-resistant, polypropylene extra wide back and seat hold up to 650 lbs. static weight PREMIUM MATERIAL: All-weather composition with dry-assist technology ideal for indoor and outdoor events; Non-marking plastic floor caps prevent damage to indoor hard flooring surfaces COMPACT & VERSATILE: Easily cleaned with no assembly required; Nesting design allows chairs to stack up to 50 high from the floor for storage, transport, or flooring maintenance PRODUCT MEASUREMENTS: Overall Size: 19.75"W x 22"D x 34.5"H; Seat Size: 17.75"W x 17.75"D x 18"H; Back Size: 19.75"W x 18"H; No Assembly Required