Mesh high-back chair comfortably supports up to 450 lb. with normal use. Generous seating proportions and adjustable lumbar support provide exceptional comfort. Chair also features padded arms that adjust in height and width and a five-star base with smooth-rolling casters. Functions include pneumatic seat-height adjustment, 360-degree swivel, knee tilt, tilt tension and tilt lock. Seat measures 21-5/8" wide x 20" deep while back size is 22-3/4" wide x 28" high. Seat to floor measures 19-1/4" to 22". Usable seat depth is 19-3/4" deep.