[Ergonomic Chairs]: Built-in solid lumbar support and ventilated curved backrest greatly fit your spine. Proper posture effectively relieves your back pain and leads to better long-term comfort. An ergonomic desk chair keeps you more productive at work. [Multi-function]: Pneumatic adjustable height, 90° flip up armrests, 30° rocking mechanism, and 360° swivel. The reclining system allows you to tilt the backrest back to achieve a comfortable position. With the flip-up arms, the office chair can easily slide under a desk to save space when not in use.