Office Chair Gas Lift Cylinder- 550lbsAdjusting Chair Gas Lift Cylider: The cylider can be adjustable. The fully expanded height is 11 inch, the cylinder height is 6 inch, travel from the highest to the lowest point, replace your office chair gas cylinder and stop worrying about disturbing anyone,360 degree rotation to all directions, freely lift and rotate your office chair smoothly and quietly. Easy Installation: Usually you may need to use a rubber mallet to take out the old gas lift