Mid-back chair features a mesh back & built-in lumbar support that easily adjusts to enhance your comfort. Armrests with a steel frame adjust 2-1/2" in height & are covered with polyurethane pads for your comfort. Dual-action synchro tilt allows the back to recline at a two-to-one ration to the seat angle so you can recline while keeping the seat cushion relatively level to the floor. Other functions include four-position tilt lock / unlock, seat-depth adjustment, 360-degree swivel, tilt tension & pneumatic seat-height adjustment from 16-3/4" to 19-1/2" high. The seat is upholstered with fabric & measures 18-1/2" wide x 18-1/2" deep. Back size is 18-3/4" to 22-1/4". 27-1/2" diameter five-star base is made of nylon & is equipped with 60mm dual-wheel casters for easy chair movement. Weight capacity is 250 lb.