DIN 8912
DIN 8912 Coupling nuts and screwed plugs for use with PN 40 flared flange solderless compression couplings in refrigerating systems
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 06/01/1990
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 06/01/1990