Pneumatic seat height adjustment from 16" to 21" with paddle lever control. Black polyurethane foam seat won’t crack or peel. 2" nylon carpet casters. Seat: 14" diameter. Manufacturer’s limited lifetime warranty. Shpg. wt. 16 lbs. Manufacturer’s limited lifetime warranty. Assembly required. Alternative casters are available to meet your specific needs. Casters supplied with this chair are not suitable for all floor types.