That would be used on the '79 and up CB650, CB750, CB900, and CB1100. It will work on the earlier models with a little work. Definitely worth it, though, because it's fully electronic instead of the electro-mechanical one that is stock.
Check my sig for another way to hook up a cheap and reliable reg/rec to your bike. The wiring should be the same, though the letter designations would be different.