Adjustable Seat Height Experience Orrsaker use a high-quality gas lift for this tall drafting chair, adjust seat height to suit various needs. We help you find the right leg position to promote better blood circulation and reduce fatigue Supportive 2-Inch Lumbar Support It features an ergonomic X-shaped frame design that enhances stability of the backrest. Our Orrsaker tall ergonomic office chair includes supportive lumbar support, with a 2-inch range for accommodating different heights Cool Sitting Experience Comes with a mesh back that prevents sweating and discomfort during extended periods sitting. This tall office drafting chair design not only supports your back but also promotes better airflow, reducing any sense of stuffiness Stable & Durable Construction It is designed with silent PU casters for smooth 360 rotation, ensuring your floors remain scratch-free. It features a sturdy class-3 gas lift and a thickened explosion-proof base plate. Max capacity is about 300lbs Easy Assembly Experience We provide necessary screws, tools and an installation manual to help you solve installation problems.