I have seen these tiny guns several times over the years. They are usually silver toned and usually a fob or charm. These working guns were originally sold with tiny ball ammunition and stoppers and fired very powerfully for their size. Not deadly but I wouldn't want to get shot by one! They were made in Germany around the 1950's, and were beautifully and intricately made. These derringers are rare gold toned and are 1 9/16 inches by 11/16 inch tall. You can cock the hammer and pull the trigger. They are marked Maus Germany and are in nice condition.