Our ergonomic polyurethane tractor stools feature your choice of black rolling, non-marring casters (suitable for both hard and carpeted floors) or black, non-marring bell glides (suitable for both hard and carpeted floors) on a nylon-reinforced fiberglass base. Our rugged polyurethane round seat is self-skinning, chemical- and puncture-resistant, and fully washable. Optional foot rings are available in 18 1/4-inch diameter, black, nylon-reinforced fiberglass or 18-inch diameter chrome. Each ergonomic stool is backed by our 15-year warranty, lifetime on the pneumatic cylinder.