Pneumatically adjusts 8" up or down while seated. Overall height adjusts 19" to 27". Contoured, black polyurethane self-skinning foam seat and back won’t crack or peel with wear. Large nylon reinforced base with 20" diameter chrome-plated adjustable footring and 2" high-impact nylon-reinforced glides. Independent paddle levers control 22° back angle and 10° seat tilt adjustment. Back adjusts 5" in height. Seat: 18-1/2w x 17d. Back: 15-3/4w x 12h. Shpg. wt. 36 lbs. Assembly required.