Office Chair Presidential Beautifully upholstered In black LeatherPlus. LeatherPlus is leather that is polyurethane infused for added softness and durability. Passive ergonomic seating with built in lumbar support. Upright locking positions. Pneumatic gas lift seat height adjustment. Adjustable tilt tension control. Large 27 nylon base for greater stability. Hooded double wheel casters. Available for Online Purchase Only. Assembly required. This product ships direct from the manufacturer, so RC Willey Delivery is not available.