MySit 6 Stroke Gas Lift Cylinder for Herman Miller Aeron Chair Replacement Parts, Heavy Duty 450lbs New Pneumatic Cylinder, Gas Cylinder, Class 4, Ref Code 1B65LR. CLASS 4 LEVEL GAS LIFT CYLINDER — This heavy duty gas lift cylinder made with high construction industry standard (BIFMA Plus Qaulity) for Herman Miller Aeron Chair cylinder, ref code 1B65LR. ADJUSTABLE HEIGHT 6 INCH — Adjustable Height 6 Inch, the fully expanded height is 16 inch, the fully compressed height is 9.9 inch. Please Check the production date under seat of the chair. DIAMETER — small black tube diameter: 1.1″ (28mm), middle chrome tube diameter 1.3″ (33mm), outside big black column diameter: 2 (50mm). REPLACEMENT PARTS FOR HERMAN MILLER AERON CHAIR — Please check the cylinder by opening the mechanism box under seat before purchasing. If the Cylinder has a cable pin hook on the top of the cylinder that this version will workable. If the Cylinder has a cable plastic actuator on the top of the cylinder that this version won’t workable, please reference to other ASIN: B0CCHQYDVG. Please check the cylinder by opening the mechanism box under seat before purchasing: If the Cylinder has a cable pin hook on the top of the cylinder please reference to ASIN:B0B7QTP77K. If the Cylinder has a cable plastic actuator on the top of the cylinder please reference to ASIN: B0B7QL63KY or ASIN: B0B7QKNRX2. If you receive an item and it doesn’t work properly or you don’t like it because of any reason at all. Please wait for the result of cancellation. The order will be processed and completed by automatic warehouse system within 5 minutes. Sending direct message to cancel the order is not allowed for every case. For the return case.