Designed to fight fatigue and move easily, these tastefully styled stools will also complement office decor economically. Upholstered in black anti-microbial vinyl that's treated to fight microbes and bacteria. Easy cleaning. Rugged powder coated steel base has smooth rolling dual wheel casters. Pneumatic adjustment for 19-24" seat height range. Seat measures 16" diameter, 4" thick. Base measures 25" diameter.