JONPONY Big and Tall Office Chair, 500lbs Desk Chair, Ergonomic Office Chair, Adjustable Lumbar Support, Headrest & 3D Armrest, Thickened Cushion has a Spring Pack in The Middle,BlackTall office chair that provides 500 pounds of heavy support and comfort, the cushion is thick and wide, and there is a spring pack in the middle for added elasticity and more comfort to your office hours You can adjust lumbar support height and depth; headrest height and angle; armrest height, angle, forward & backward; seat cushion height; tilting angle up to 120 and rocking resilience to your personal most comfortable position. The breathable mesh