The Safco backless office stool adjusts to your needs and tucks under work surfaces when not in use. Other features include durable ventilated, urethane covered seat, pneumatic seat height adjustment, 3-piece telescoping dust cover and a 5-star reinforced base with dual wheel hooded casters. Additional caster options available. Meets or exceeds ANSI/BIFMA standards. Dimensions: Seat Size: 13.5"Diameter. Base Size: 18"Diameter. Seat Height Adjustment: 16" - 21"H. Weight: 15 lbs. Limited lifetime warranty from Safco. This chair normally ships within 2-3 business days.