The main purpose of any lumbar support in an office chair is to help support your back and maintain the natural curvature of your spine as you sit. Without the proper support, our bodies tend to compensate by leaning forward or slouching, leading to poor posture and back pain over time. As such, good lumbar support is one of the most important things to look for when picking out an ergonomic office chair. Product Details Back size: 21W×30L inches Seat size: 21W×19D inches Weight capacity: 225 lbs Features: 【180 ° reclining】 comfortable for lunch break, fully charged for afternoon work 【Integrated thickened headrest】 fits the cervical spine for continued comfort 【ergonomic backrest】Rejected sedentary hunting ,stiff effective protection of the spine, release of the cervical spine 【Scientifically designed lumbar support】manual adjustment of the top waist design, the angle is adjustable to solve the problem of low back pain 【Linked armrests】 automatically adjust the angle through the reclining function to give the best support for expansion 【Curved thick seat cushion】 filled with high-density sponge, not easy to collapse, improve sitting feeling 【Telescopic pedals and horizontal tilt】 provide better comfort for lunch break 【Adjustable chair height】accommodate various table heights 【Environment-friendly and healthy PU material】 providing good texture and breathability 【Move freely】360°swivel and easy move wheels, free to move around without standing up