1.321 stainless steel flange 2.Size:1/2"-100",SCH5-160 ... ,CBM1013-81,CBM1018-81,CBT47-1999· Industry Standard:JB/T74-1994,JB4700-4707-2000,JB/ZQ4485-4486-1997· Industry Standard:HG/T20592 ... die forging from round bar,CNC machining,Drilling and Passivating 321 stainless steel flange