Welded chrome steel frame and precision machined adjustment screw.14" diameter round seat.14.5"W x 9.5"H backrest is adjustable vertically, horizontally and will tilt to conform to user's body.Mounted on 2" twin wheel polyurethane casters.Height adjustment: 18" to 28".ase diameter: 21".Also available without backrest (BRT-12121) or without footrest (BRT-11122).