For those interested in the early German handguns, here is a family portrait of hand guns of the deutschen Marinen from 1849 to 1879.
From top to bottom:
M/49 Marinepistole - The first German navy pistol, 1,000 purchased for the First Fleet, the Reichsflotte created in 1848. Discussed here...
Actually, the entire text from the beginning down to, and including, the issue in Danzig is cut and pasted from a post I wrote on a Luger forum back in 2016.
That holster is NOT for the Colt revolvers. It was made for the next German navy pistol, the double-action M1869. The one on the left is for the Colt, the one on the right is for the M1869. Note the much deeper opening for the trigger guard. It is overall slightly larger.