Well said Steve. I like to talk about voltage because current confuses people. Like, the current is the same throughout the circuit, yet the voltage is different. So to avoid confusion, I just stick with volts in my explanations. I didn't think to mention that there IS a true 12 volt only coil. It is the Resistor Coil which has the ballast built in. I do not like them myself. I also don't like paint melting ballast resistors!
