The key parts of the MSQ/RSQ series stopper Cylinders are manufactured by ourselves, from die-casting, aluminum profile precision draw, machining, casting's shot blasting, air tightness assurance through the impregnation by vacuum pressure process and passivation treatment, aluminum profile surface oxidation treatment,to assembling and testing, for better quality control. The cylinder covers, piston and piston rods are CNC machined, seals are from PARKER, to ensure the cylinders work stably and safely.