Imperial German Navy clock, produced by Gustav Becker and supplied to the Kaiserliche Marine by Julius Haffner - Pola, circa 1915 and installed on board U-boats or large battleships. The clock, made entirely of brass, has a manual winding mechanism with an eight-day power reserve.
The glass porthole on the front opens through a hinge allowing access to the loading of the mechanism and the adjustment of the advance or delay of the minutes via a lever placed above the twelve o'clock position.
On the dial there are the name of the supplier J. Haffner of Pola, the Imperial German Crown of the 1st Type with "M" below (Marine) and the assignment number made up of three digits, probably referring to one of the first naval bases of the Kaiserliche Marine.
Perfectly functional and excellently preserved.