ISO 4033 Hexagon High Nuts International Standard specifies the characteristics of hexagon high nuts (style 2), with threads from M5 up to and including M36, with product grade A for threads D ≤ M16 and product grade B for threads D > M16. If, in special cases, specifications other than those listed in this International Standard are required, they can be selected from existing International Standards, for example ISO 724, ISO 898-2, ISO 965-1 and ISO 4759-1.