This is a 14.8v set point regulator with a plug for converting a pcm controlled unit, to 14.8v or 15.3v with a ignition source, or replacing a unit in your alternator. The 15.3v variant uses a diode inline on the sense wire to bring your setpoint up about .5v.
This is for Denso Hairpin type alternators only, this is something most people are capable of doing with basic hand tools and a soldering iron. We also have write ups on same replacement on our facebook GROUP PAGE.