CQ2 series type compact cylinder, with bore size from φ12mm to φ100mm; Compared with old type, new type cylinder is with lighter weight and uses less material; Small auto switches can be mounted on any of the 4 surfaces two surfaces for( φ12 to φ25) to get more flexibility; The outer dimensions of the cylinder do not change whether the auto switch is mounted or not, which is much more easy for machine design.