Beautifully upholstered in black Leather. Leather is polyurethane infused for added softness and durability. Passive ergonomic seating with built-in lumbar support. Padded armrests covered with Leather upholstery. Large 27″ nylon base for greater stability. Hooded double wheel casters. Upright locking position. Pneumatic gas lift seat height adjustment. Adjustable tilt tension control. Optional knee-tilt mechanism available (B7502).