D.R.G.M. Pen Gun
I don't know really whether it is a one. I didn't find any Information about it. I send you its PICs as attachment. It's all 12,5 Cm long with letter "Existence DEPOSE D.R.G.M. RO 769646" as D.R.G.M. stand for "Deutsches Reich Gebrauchsmusterschutz" (something like Patent no. in Germany before WWII)and RO for Romainian. It means, it was manufactured in 1920's or 1930's. The Chamber adapt .45 bullet exactly. But I think that it is not the real one, because they have used Bottle Chamber at that time. I hope you can help me more to find more about its history.
Photo and information from: Kevin (If you have information about this please send to Kevin at: firstname.lastname@example.org)