Flash Furniture High Back Black Leather Executive Swivel Office Chair With Triple Paddle Control And Lumbar Support KnobThis ergonomically designed office chair offers plenty of adjustable features to get to your desired comfort level! The triple paddle control feature controls your seat height, back tilt position and knee tilt. The locking back angle adjustment lever changes the angle of your torso to reduce disc pressure. The most valuable feature of this chair is the controlled lumbar knob that allows you to increase and decrease the pressure provided to your back.