No clue, My guess would be some sort of DET tool.
That's an odd one and no mistake Bob. The soldered on head section very much puts me in mind of a radiator bleed key, but the actual socket shape doesn't match up. It does seem very vaguely familiar but I can't place it.
You have been finding some lovely tools... thanks for sharing them. Question; do you find them in such good condition generally, or do a load of cleaning and buffing before we get to see them?
The brass tool leans toward a nautical use. The sockets seem too specific for a DET.
unknownSmall hammer tool made completely from brass. Folding knife blade and corkscrew are made from steel and then bronze plated. Probably a cocktail/bartenders tool for cracking ice? I bought it from a seller in the U.K. who had no idea of it's origins. Hopefully you guys (Al) can figure this one out for me too.