Giantex Home Office Desk Chair, Mid Back Swivel Chair with Hollow Design & Height Adjustable (Yellow)[Adjustable Height & Rocking Mode]: According to users different heights, you can use the lever to easily adjust the seat height of this desk chair from 18 to 22. More than that, using the control knob under the seat to adjust the rocking tension, you can relax more during work breaks under the rocking mode. [Hollow Back & Comfy Materials]: The seat of this swivel chair is covered with high quality leathaire, which is breathable, skin friendly and