Transform your work-space seating with the Optimus Big and Tall Chair. Designed with every shape and size in mind, Optimus brings a comfortable seating experience to everyone. To ensure you get the proper support and most relaxing seat for 24/7 needs, the design features a 400 lb. weight capacity with numerous mechanisms. Functions include pneumatic seat-height adjustment from 19"" to 22"", back-height adjustment, back tilt lock and 360-degree swivel. Optional T-pad arms (sold separately) adjust in height and width. Five-star base is oversized for stability and equipped with 2-1/2"" diameter, dual-wheel carpet casters that roll easily from workstation to workstation. Seat size is 23"" wide x 22"" deep. Back measures 22"" wide x 25"" high.