DS DS/EN ISO 4014
DS DSEN SO 4014 2011-MAY-02 Hexagon head bolts - Product grades A and B
ISO 4014:2010 specifies the characteristics of hexagon head bolts with threads from M1,6 up to and including M64, of product grade A for threads M1,6 to M24 and nominal lengths up to and including 10 d or 150 mm, whichever is the shorter and product grade B for threads over M24 or nominal lengths over 10 d or 150 mm, whichever is the shorter.