DIN 2247-2
DIN 2247-2 Geometrical product specifications (GPS) - "NOT GO" plug gauges - Part 2: With rod gauge for holes over 40 mm up to 500 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