Deluxe Breathable R2 SpaceGrid Back with Adjustable Lumber Support. Thick Padded Black Mesh Seat. Pneumatic Seat Height Adjustment. Self Adjusting Mechanism Adjusts Tilt Tension by Using your Body Weight as a Counter-Balance Resulting in Perfect Balance as you Recline. Mechanism also Features Backrest Lock and Anti-Kickback. Platinum Coated Padded Flip Arms with PU Pads. Heavy Duty Platinum Coasted Base with Black End Caps Oversized Dual Wheel Carpet Casters.