Gave me an idea. I have an old 12volt drill and newer 18volt tool set.

The 12volt battery is long dead and really no reason to try to replace it. But it would be a handy car/boat/wherever tool by putting a cigarette lighter adapter on it with a real long cord.

Thanks Greg. (I had been thinking of making it a plug in with an old power adaptor "wall wart," but a 12v portable makes even more sense)