These coils are designed for use with a demountable transformer and are wound on rectangular insulating bobbins with an overall height of 70mm. The coils are wired to a panel mounting, with the earth pin connected to the front panel and a 4mm socket. All connections are fully enclosed within the panel housing for safety. This particular coil has 500 turns, a current rating of 0.5A, and a resistance of 8.95 ohms. A separate mains connector with a moulded plug is supplied with each coil.