DOZYANT Gas Lift Cylinder, Office Chair Gas Lift Cylinder Replacement,Hydraulic Pneumatic Shock Piston Heavy Duty (450 lbs) Universal Size Fits Most Executive Chairs, Highest End Class 4 HEAVY DUTY Gas lift cylinder that holds great weights - tall center support column of the chair. Holds up to 450 lbs on most office, executive and computer chairs.Highest End Class 4 gas cylinder on market. STANDARD CYLINDER DIAMETER: Outer cylinder: 2 inches, Inner cylinder: 1.1 inches. Please confirm the measurement before ordering. SMOOTH & NOISELESS: Full 360 degree rotation, smooth and noiseless movements to all directions 5 STROKE FOR ADJUSTING CHAIR HEIGHT: Minimum length: 10 inches; maximum length when fully extended: 15 inches; adjustable range: 5 inches EASY INSTALLATION & 5 YEAR WARRANTY: Can be installed easily with no additional screws required. Comes with 5 year warranty.