... .1/8-6" 3.Connection:NPT thread 4.Heavy/Standard/light weight Union, 3/4 In, NPT, Black Malleable Iron Specification:Union ... , 3/4 In,Connection NPT threads, Material of Construction Black Malleable Iron, ... Test:Test Pressure:25kg/cm2Working Pressure:16kg/cm2Chemical PropertiesC:2.4~2.9 %Si:1.2~1.7 %Mn:0.3 ...