This is a D/C regulator / rectifier for the SIP VAPE ignition systems to convert your VAPE ignition to DC all you need to do is change over to this regulator (you will also need a suitable battery and wiring - how to do this is in the original handbook that came with the VAPE system).
 
It's a little more complicated with the PX's what originally had 7 wire stators, see the guidance on the SIP website to navigate around this.