... .size:1/2",3/4",1" 3.ISO9001:2000 brass air valvesTechnical requirement:1.Before assembling,all parts will be cleaned ... .3.Handle turn or close freely4.After assembling,test by air at pressure no less than 0.8Mpa,no leakage.High ... Valve Factory welcome to your inquiry!Tel:86-13777616101Wendy brass air valves