Contemporary ergonomic mesh back designed to provide exceptional back support and to prevent body heat and moisture build-up. Ratchet back with active lumbar support. Height and width adjustable arms. 3 paddle multi-function tilting mechanism, which allows the seat and back to be independently adjusted and locked in any position. Seat tilt lock allows the seat to lock throughout the tilt range. Adjustable tilt tension control. Pneumatic gas lift seat height adjustment. 27" nylon base. Hooded double wheel casters.