I just finished building another high end coil for a friend. He wanted a keyed safety switch added and a top of the line PID controller that didn't look so "Industrial". He was so happy with the finished product he is having me put 2 coils together for a couple of close friends of his. The Oil Coil features a heavy duty case, led power switch, high temp coil wand, high end PID and a low voltage keyed safety switch. The Keyed switch is wired to interrupt the power going to the coil on the low voltage side. When in the off position (horizontal) the coil will never see a rise in temperature.