DIN 2246-3
DIN 2246-3 Geometrical product specifications (GPS) - "GO" plug gauges - Part 3: For holes over 40 mm up to 120 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