Compu-Fire 32-amp Charging System 55540 Compu-Fire charging systems include the 3 components necessary to keep the battery charged for Evolution engines Systems include a custom wound stator with the correct engine case plug, a precision balanced rotor with the magnets permanently attached and the splined center hole designed to properly fit either OE or aftermarket engines and a black finned series type voltage regulator with the voltage output calibrated to meet maintenance free battery requirements Will also work with Evolution Style Aftermarket Engines