DIN 2247-1
DIN 2247-1 Geometrical product specifications (GPS) - "NOT GO" plug gauges - Part 1: For holes from 1 mm up to 40 mm nominal diameter
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 07/01/2008
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 07/01/2008