Type RB340 Dynamo Regulator Control Box, also known as NCB133.
This is the uprated 30amp version of this control box, often found in vehicles with higher specification electrical equipment.
The RB340 control box superseded the RB310 and was commonly found in a wide range of popular British vehicles, including Austin, Jaguar, MG and Triumph products.
Alternate codes: MBU1212, 37H6959, GEU660.
