This standard BS G 175:1959 Aircraft fuel nozzle grounding plugs and sockets is classified in these ICS categories:
49.100 Ground service and maintenance equipment
This British Standard specifies requirements for plugs and sockets to provide an earth connection for aircraft refuelling couplings.
NOTE Where metric equivalents have been given, the figures in British units are to be regarded as the standard. The metric conversions are approximate. More accurate conversions should be based on the tables in BS 350, “Conversion factors and tables.”