Hm... can you please give the reason why it wont work with the regular inverter unit? I rebuild my civilian SS20 IWS from scrap to running order over the years. First i used a self made proprietary battery cap that had no brightness control and it worked fine. Recently acquired one of these regulated ones from a guy from said online auction platform and it worked well too. All with using the same inverter piece. But i can't tell what kind of inverter it is because i acquired the IWS from some greek guy who doesn't know anything about it or even what it was in the first place.