After a long search, get a Zenith wrist alarm. As described in the Rössler-book on page130. About 1920. Silver case, 46 mm diameter. Enamel dial (unfortunately slightly damaged).
And photos of a Chronometer 2000 with a very easy movement. Calibre 135-1-0. Serial number 6833969. Probably around 1969.

 

Thanks for the photos! I like the wrist alarm, very cool!

 

Wow. Where did you find that zenith alarm. Beautiful. Been after one myself. Missed one with a great condition dial a while back (I thought nobody would buy it, I was saving). Probably my favourite watch I dont own.