The XMSJ Ergonomic Office Chair is expertly crafted with an S-shaped backrest, headrest, and lumbar support to perfectly fit the contours of your body and provide ultimate comfort for your back. With nylon wheels that can rotate 360 degrees and glide quietly on any surface, this chair offers optimal functionality. It also features five humanized adjustments for you to find your ideal sitting position, including adjustable armrests, lumbar support, headrest, seat height, and swing range. Made of premium polyester mesh and filled with high-density sponge, this chair is both durable and breathable. Meeting Grade 3 SGS certification, the height-adjusting GAS rod is secure and stable. The heavy-duty base and smooth rolling casters ensure excellent stability and mobility, with a maximum weight recommendation of 225 pounds. Assembly is hassle-free with the included instructions, and adjusting the cushion height and backrest is easy with the lever and knob controls.