Historical
DIN EN ISO 8674:2013
Hexagon high nuts (style 2) with metric fine pitch thread - Product grades A and B (ISO 8674:2012); German version EN ISO 8674:2012
This document specifies the characteristics of hexagon high nuts (style 2) with metric fine pitch thread, with nominal thread diameters D from 8 mm up to and including 36 mm, with product grade A for sizes D smaller than or equal to 16 mm and product grade B for sizes D larger than 16 mm.
Deutsches Institut für Normung [din]