DIN 7818
DIN 7818 Rims for motor vehicles, trailers and agricultural vehicles; flange C, D E and F; rim diameter code 14 to 20
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 03/01/1982
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 03/01/1982