This Princton 21j twin barrel was donated by a friend to my collection.
It came to me with a slight problem, the hour gear had 2 teeth missing.
Didn't know that until I opened it up quickly finding the missing teeth and discarding them, I removed the hour tube from the gear and found another matching gear in my parts bin, did a little swap by drilling the new grear and press fitting the old tube on.
It seems that parts may be more interchangable than I had thought with some fitting.
Working great and keeping very good time, this one has a 21j Slava 2414 twin barrel movement and is being tested for duration I am expecting at least 40+ hours