Seat height range is adjustable with a pneumatic lift for counter, table and desk applications. Infinitely locking articulating back with tension-controlled back mechanism. Welded steel 5-star base with telescoping polypropylene cover and floor glides. Chair measures 24"W x 24"D x 28-1/2 to 34-1/2"H overall. Solid molded self-skinned polyurethane seat and back in Black. Some assembly required.