This is a solid state rectifier regulator and capacitor all in one, it is a cost effective and efficient way to replace both your old Lucas rectifier and Zener diode regulator and alloows you to run without a battery. This is suitable for single phase 12V systems, and both positive and negative earth. To take a look at the installation instructions, please click on the second and third image, as this can also be used to convert a 6V to 12V. This will work with practically all three or four wire stators, but not the five wire Energy Transfer type.