I'm a sucker for steel cased watches, so I couldn't pass up this little deco treat, blued steel moon hands were a plus.
The serial # dates it to pre-WWII; very nice!! Those blued hands make it pop! And that movement looks great for a 70+ year old...not even any arthritis. Congrats!
It is a CK 805, a model launched in 1929. Mine dates from around 1934 (case ref 8808XXX, slightly older than yours) : IMHO one of the most beautiful 26.5, and among the first I acquired. Here in a 1930's - exact year still unknown to me- british advertising folder (a sturdy Watch, especially suitable for sportsmen!) : The same case design was used for the ref MN742 named 'agrafe' (staple) , the non wristwatch that one could clip to his belt or Inside his pocket for playing golf and put on its desk as a deskwatch, and it is alo very desirable. Mine is in very good condition with its original dial and crown : Here in a 1933 catalog :