I was told the maker is Srb & Stys, Prag or bmk. What is correct? Belongs to the Kriegsmarine Artillery. It is marked with "Artl." (Artillerie), the eagle and "M" (Marine) on the left and "N" (North Sea), "DF7x50" (Doppelfernrohr) together with the number "3392" on the right. I hope the pictures are okay to make an estimation. As far as I can see, these binos have never been opened and are still in untouched condition. Thank you very much for the help/interest.