Sihoo M57 Ergonomic Office Chair with Breathable Mesh CushionSihoo M57 ergonomic office chair is a high performance mesh office chair that takes into account the ergonomic sitting position and uses advanced technology. It has multiple adjustabilities, from the headrest, lumbar support, 3D armrests, seat height, recline, and recline tension, to help you maintain the optimal seating posture and enjoy a healthy work experience. Key Features: Supports up to 330 lbs 3D adjustable armrests for versatile comfort