Office Star 5500 Dillon Back & Seat Managers Chair - Black Vinyl Seat - Black Vinyl Back - 5-star Base - Armrest - 1 Each The 5500 basic design of Dillon Back and Seat Managers Chair is an excellent example of simplicity at its best. AirGrid Back with built-in lumbar support conforms to your back for passive ergonomic support. Seat is thickly cushioned for enhanced comfort. Both seat and back are upholstered in vinyl for easier cleaning and longer-lasting use. Functions of this professional chair include One Touch pneumatic seat-height adjustment, 360-degree swivel and 2-to-1 synchro tilt control with adjustable tilt tension. Angled arms with soft pads are height-adjustable. Heavy-duty, angled nylon base has oversized, dual-wheel carpet casters.