I have a side by side 16ga that I inherited from my grandfather and I was hoping to get more information on it. The top of the barrel is marked "Firma Franz Kettner" on one barrel and "Koln-Suhl" on the other. There is also the word "Nitro" engraved under each barrel. Under the forestock it is marked "KRUPP" along with what appears to be a makers mark and "SS" stamped in each barrel with a "W" on one barrel and the number 2439. I can also see a mark with a crest with a crown under it and a U under that. There is also a "W" with a crown above it, the number 16 inside a circle and 16/1 next to it. I will attempt to get some pictures posted in the near future. Any and all help is greatly appreciated. Facebook Photo Album