Ergonomic Office Chair:1.Wider and higher backrest with breathable nylon mesh, ergonomic waist support design can support back,especially suitable for people with poor lumbar spine to slow down the pain caused by long sitting.2.Seat cushion designed by the shape of human buttock,made by molded foam with strong resilience,solve the hip discomfort caused by people sitting a long time.3.Height adjustable armrests with soft thicken foam,it feels good when you put your arms on it. Comfort:Breathable nylon mesh back, soft seat cushion made by 4.5inch high quality molded foam cant be deformed by siting long time.Nylon mesh and molded foam greatly improve breathability and comfort, avoiding a stuffy feeling, especially in the hot season.Suitable for working more than 4 hours,like IT engineers, mechanical engineers,online game player and so on. Function:1.Height adjustable armrests with soft thicken arm cushions, adjust the height range through the push of a button. 2.The back is independ