PU Leather Hydraulic Lift Adjustable Height Swivel Office Desk Chair Black (1804-5) Swivel Seat -so you can turn around while sitting, Tilt Tensions -so you can lean back, Hydraulic Lift -so you can go up and down, Rolling Chrome Base -so that you can move easily around the room. Seat Height :15" - 22", Back Seat Height: , Seat Width :20.5", Seat Depth: 18.5". Weight Limit 250 Pounds 6' Tall UPDATED VERSION: customers have told us in the past that the regular wheels do not work well on hard (wood) floors and so we upgraded the wheels to higher quality rubber/plastic so that they will work smoothly on hard (wood) and soft (carpet) floors. We have also added memory foam so it is more comfortable.