150 coupling fitting 1.Size:1/8''~4'' 2.Material:SS316,SS304 3.Thrreaded:NPT,BSPT,BSP,DIN2999,ISO228/1 Stainless Steel 150 coupling fitting:1.Size:1/8''~4'' 2.Material:SS316,SS304 3.Thrreaded:NPT,BSPT,BSP,DIN2999,ISO228/14.Pneumatic pressure testing is performed on every fitting manufactured;5.Material chemical composition analysis by spectrometer on every furnace before casting is strictly ...