scope:

Scope and field of application

This standard specifies dimensions and technical delivery conditions for M8 to M52 hexagon fit bolts, assigned to product grade A (for size M10 or less) or product grade B (for size M12 or greater).

For hexagon fit bolts of sizes greater than M39, the specifications of this standard apply only with regard to dimensions and tolerances, the other properties being subject to agreement.

NOTE: For sizes M10, M12, M14 and M22 bolts, this standard specifies widths across flats which are in current use, i.e. 16 mm, 18 mm, 21 mm and 34 mm, in accordance with ISO 272. Specifications for obsolete widths across flats (17 mm, 19 mm, 22 mm and 32 mm) are provided in Appendix A.