Mid-back chair features a body weight-control mechanism that moves with you. This chair control allows your body weight to recline the chair and return the chair to its task position for easier control. Self-tilt tension adjustment offers five locking positions. Other functions include 360-degree swivel and pneumatic seat-height adjustment from 18-1/4" to 22-1/4". The height-adjustable arms are covered with polyurethane pads for your comfort. Recline easily with the mesh back and seat upholstered with fabric. 27-1/6" diameter spider base is made of nylon and equipped with five 60mm dual-wheel casters for easy chair movement. Weight capacity is 275 lb. Seat measures 19-1/8" wide x 17-1/8" deep. Back dimensions are 19-9/31" wide x 21-6/23" high.Mid-back chair features a body weight-control mechanism that moves with you. This chair control allows your body weight to recline the chair and return the chair to its task position for easier control. Self-tilt tension adjustment offers five locking positions. Other functions include 360-degree swivel and pneumatic seat-height adjustment from 18-1/4" to 22-1/4". The height-adjustable arms are covered with polyurethane pads for your comfort. Recline easily with the mesh back and seat upholstered with fabric. 27-1/6" diameter spider base is made of nylon and equipped with five 60mm dual-wheel casters for easy chair movement. Weight capacity is 275 lb. Seat measures 19-1/8" wide x 17-1/8" deep. Back dimensions are 19-9/31" wide x 21-6/23" high.