that Zenith is a beauty.
i'm very ashamed to say that my fingers and thumbs fiddling with the
balance were the reason i had to throw one of those in the trash instead of
getting it serviced like i should have done.
luckily it was a long long time ago so values were different and it did
eventually teach me that i will never make a watch repairer.
there are so few around now that i should have kept my fingers out of the
internals
look after it chronomtr as they are a superb piece of aviation and
horological history.
best
G