Adjust seat height, backrest height, and footrest to provide ideal working comfort from this ERGOCRAFT Contoured Stool. Pneumatic seat height adjustment. 27" dia. high-impact molded black plastic base with dual-wheel hooded casters. Contoured waterfall seat relieves leg stress. Backrest has built-in lumbar support. Meets or exceeds ANSI/BIFMA standards. Made in USA.