This Standard establishes a preferred series of metric thicknesses, a preferred series of metric widths, and a preferred series of metric lengths for flat metal products of rectangular cross section. The thicknesses and widths shown in this Standard are also applicable to base metals that may be coated in later operations. This Standard also establishes a preferred series of metric sizes for round, square, rectangular and hexagonal metal products. The sizes in this Standard provide an orderly series of thicknesses for all flat metal products and an orderly series of widths for rectangular cross section metal products. The series were developed to provide a reasonable selection of metal thicknesses from 0.050 to 300 mm and of metal widths from 10 to 5000 mm. In each case the series provides for some second choice sizes, third choice sizes, and sometimes some fourth choice sizes (thicknesses and widths) to cover instances where selection from the primary preferred sizes may be inadequate. Sufficient coverage in logical steps is presented in the tables to adequately serve most of the general purpose requirements of industry for flat metal products. The Standard also provides an orderly series of lengths for flat metal products. This Standard also provides a series of sizes for each of round, square, rectangular and hexagonal forms of metal products used for general applications. The series were developed to provide a reasonable selection of metal diameters from 0.020 to 320 mm for rounds and distance across flats from 3 to 300 mm for squares, various cross section sizes from 1.6 by 2 to 100 by 200 mm for rectangles, and from 1.5 to 150 mm for hexagons. The series provides for some second, third and fourth choice diameters for rounds and second and third choice distance across flats for squares and hexagons where selection from the primary preferred sizes may be inadequate. The series also provides for preferred lengths of rounds, squares, rectangles and hexagons. Sufficient coverage in logical steps is presented in the tables to adequately serve most of the general purpose requirements of industry for round, square, rectangular and hexagonal metal products.