Wound on rectangular insulating bobbins, overall height 73 mm. These coils are wired to a panel mounting. The earth pin is wired to the front panel and 4mm socket. all connections are completely surrounded by the panel housing. A separate mains connector with moulded plug is supplied with each coil. a 50 turns 230V d 500 turns 230V b 100 turns 230V e 1000 turns 230V c 200 turns 230V f 2000 turns 230V