Ergonomic Lumbar Support: Your entire back is perfectly supported by the integrated lumbar support. By turning the control knob located on the right side of the backrest, you can modify the support's height and depth. Adaptable Headrest Height: The user can customize the height of the headrest to suit their preferences. It offers ideal neck support and relieves pressure. 90°–135° Backrest: The Master Series chair can be customized to the user's preferences with a backrest angle ranging from 90 to 135 degrees. Microfiber Upholstery: Microfiber is resilient, stain-resistant, and soft to the touch. Silicone skin: a material that is both healthy and environmentally friendly, and it lasts for seven to fifteen years despite constant wear and tear. Size recommendations: up to 6'3" and 275 pounds.