The Deluxe Air Grid Seat and Back Chair offers a modern style and multiple ergonomic adjustments to keep you more comfortable while working. Breathable Dark Air Grid Back is equipped with built-in lumbar support. To further your comfort – this office task chair features polyurethane arms that adjust in height and width. Chair also features pneumatic seat-height adjustment from 19″ to 23-1/2″. The heavy-duty – angled nylon base is equipped with oversized – dual-wheel carpet casters. Seat measures 20″ wide x 20″ deep. Back size is 20″ wide x 19″ high.