Since the Otto Hoffmann pin I recently posted has been declared a fake, I have replaced it with THIS one, which with its wear and patina looks good to me. ( But so did the other one - fortunately I got them from a reputable dealer who agreed to swap! ) It's an RZM marked example, but I can't make out the M1/?? mark ( 13 possibly? ); Hopefully someone with more experience than I have with these can determine its authenticity and manufacturer.