stainless steel flanges 1.materials:201,301,304,316,etc 2.ISO certification 3.Standards: /ASTM/ASME/ ... #-2500#2 Grade : Grade : 301, 321, 304, 304L, 316, 316L, 317, 317L,310s etc3.Standards: /ASTM/ASME/DIN/JIS ... size DN10-DN 1200,150#-2500# grade321, 304, 304L, 316, 316L, 317, 317L,310s,904L etc.standard/ASTM/ASME/ ... make new products according to your drawingsPictures shows: 316 stainless steel flanges