Ergonomic features make these BEVCO Continuous Use Standard Industrial Stools your choice for all day use. Contoured, self-skinned polyurethane seat and back promote proper posture. Backrest supports lower back and spine. Sturdy reinforced plastic base. Height adjusts pneumatically. Footring and backrest height adjust manually. Recommended for 24-hr. continuous use with 12-year guarantee (lifetime guarantee on cylinder). Meets or exceeds ANSI/BIFMA standards. Made in USA.