This standard is included in DIN Handbook 3 E. All dimension standard are built up on the type of flange concerned. Flanges with the same nominal dimension and nominal pressure can be used for joining together pipes of all materials (cast iron, steel, non-ferrous metals). Steel flanges, the attachment of which to the pipe depends on the outside diameter of the steel pipes used, have 2 different hole sizes specified for each nominal width, since for each nominal width it is necessary to consider 2 pipe outside diameters, with the exception of nominal widths 65 and 80 and all nominal widths over 1000.