... Thread Safety Valve:Descriptions:1.A21F, A21H-C type are used for the equipment or pipeline ... medium whose working temperature are less than 200 °C.2.A21W-P, R type are used for the ... medium whose working temperature are less than 200 °C, as the overpressure protection device.3.KA21Y ... 16C,16PA21H-16C,40A21W-16P,40P15121520M27×1.5G1/2"3035766620162025M33×1.5G3/4"3540876825182531M39×1.5G1"4050100105A21Y ...