This office chair is equipped with adjustable headrest, comfortable lumbar support and height adjustable armrests, which will meet needs of different people. The entire back of the chair is designed in accordance with ergonomic theory to provide comfortable support for your back and relieve the pressure on the muscles of the various parts of the back. More importantly, this ergonomic office chair can help to improve your sitting posture, more conducive to the health of the spine of sedentary office workers. Features Ergonomic Lumbar SupportWe design the lower back support with a split curved structure, enhancing the natural curve of human spine and promoting a healthy posture. Thus, when you lean on the chair, you can adjust the angle of the lumbar support make it offer full support and fit your body. Also, the waterfall shaped cushion reduces stress on your buttocks and thigh, for that truly ergonomic experience. Large Seat & Comfortable - The mesh office chair has an extremely larger back and wide seat, and the seat slides to increase the sitting depth by 4.5cm, the whole chair measures about W67*D67*H118-128CM, the seat size: W49*D50*H50-60CM, the whole back size: L57*W50, with a loading capacity of up to 200kg. Breathable Mesh & Lockable Tilt Back - You can tilt the chair back and lock it at 4 different positions for that unique stress-free experience on your back. Unique mesh design to keep the air circulation going and the high-quality mesh resists abrasion and transformation, so that you can sit on the rolling task chair for 8 hours or more. The mesh surface is pretty flexible, skin friendly and easy to clean, so that you do not have to spend more time on cleaning. Adjustable Armrest & 3D Headrest - The arms of the ergonomic office chairs can be adjusted up & down(5cm) as per your sitting posture, which are sure to fully support your arms. This chair's headrest allows you to rotate it to a specific angle, and go up or down until it reaches a suitable height for you., so that the stress on the neck and shoulder is minimized. Smooth Movement & Stability - Ergonomically designed heavy-duty chair moves easily with 360-degree swivel caster wheels. It could run smoothly on tile, wooden floors, carpets, and other floorings. The 5-star base is made of strong material to offer you great stability. Easy to Install- All the tools are included, with which you will be able to set the comfortable desk chair up within 25 mins. Specifications Colour: Black Back type: High back Seat material: Mesh Base material: Metal Overall dimensions: 67cm x 67cm x 118-128cm Assembly required: Yes Number of packages: One Package Included: 1 x Office Chair 1 x Instruction