Historical
IEC 61076-2-104 Ed. 1.0 b:2008
Connectors for electronic equipment - Product requirements - Part 2-104: Circular connectors - Detail specification for circular connectors with M8 screw-locking or snap-lockin
"IEC 61076-2-104:2008 describes circular connectors M8 screw-locking or with nominal diameter 8 mm snap-locking, typically used for industrial process measurement and control. These connectors consist of fixed and free connectors either rewireable or non-rewireable. Male connectors have round contacts diameter of 1,0 mm."
International Electrotechnical Commission [iec]