Boss Horizontal Mesh Back Task Chair, Aluminum Arms/Base (B6566AL-BK) EachThe horizontal mesh back task chair is designed with comfort and ease in mind. The chair features a technology called a Synchro Tilt Mechanism. This allows the backrest and seat to tilt in unison. The back tilts more than seat and is also tension adjustable. The chair also features aluminum arms and base, a pneumatic gas lift that allows for easy adjustable height and a weight limit of 275 lbs. making sure it is the perfect chair for most everybody.