[Adjustable Height 4 inches]The sinking length is 2.4" (60mm), lowering the chair's minimum height, as a replacement for people needing a shorter chair. Compressed height is 7.48 inches (190mm), the fully expanded height is 11.2 inches (284mm), Stroke Length is 4 inches, which allows your chairs to rise higher. [Universal Fit Size for Most Chairs]The outer column cylinder diameter connected to the base is 2 inches (50mm), and the piston shaft diameter connected to the chair is 1-1/8" (28mm). This pneumatic piston cylinder will fit almost every office chair on the market. [Upgraded Class 4 Gas Cylinder]office chair cylinder replacement is made of premium steel, the lift has a maximum capacity of up to 1000 lbs. [Eliminate Sinking Concerns]Prevent sinking issues by removing the old cylinder using a hammer or wrench. Simply assemble our cylinder into the base and attach the seat. Our office chair lift provides seamless 360-degree rotation. [100% Satisfaction Guaranteed]For any issues with using our chair shock replacement, please don't hesitate to contact us. We are here to provide guidance, offer replacements, or process refunds, depending on your specific case. Your satisfaction is our priority. Color: Black Material: Metal Package Contents: 1*Chair Cylinder