Stainless Steel Flange ANSI Material: Stainless steel (304ss 316ss,321ss, etc.) Materials: 304, 304L, 306, 306L, 317, 317L, 321 and 904L stainless steel Types: WN, BL, PL, SW ... , SO and RF Relative Standards of Flanges: 1) DIN ... PN6-PN100, 150LBS-2500LBS Sealing Surface: F.F., R.F., and R.T.J., FM, Lap Joint