Stainless Steel 904L Weld Neck Flange, Blind Flange, Socket Weld Flange – Materials Stainless Steel Flange SS 304/304L/304H Flanges SS 310/310S Flanges SS 316/316L/316H Flanges SS 317/317L Flanges SS 321/321H Flanges SS 347/347H Flanges SS 904L Flanges Stainless Steel Pipe Fittings SS 304/304L/304H Pipe Fittings SS 310/310S Buttweld Fittings SS 316/316L/316H Buttweld