This type of watch made in the 1910s to 15 was later used by the Austro-Hungarian Navy. (I can send you the documents, which do not go through the photos on this site).
The case bears the mark (U 2) the name of a type of submarine used by the German navy during the Second World War. Perhaps it was used by a submarine officer at that time?
Enamel dial with Roman numerals, chrono totalizer at noon, and seconds at six o'clock. Graduations from 0 to 300 for the chrono.
Very beautiful movement in gilded brass, with lever escapement, compensated balance wheel, micrometric adjustment of the racket.
Plain metal case.
Good condition, serviced under warranty.
I remain at your disposal for any additional information or photos.