Ambassador of the mid 30's... yellow gold version with the origional 3 chain bracelet. This along with the Commodore model... the bracelet makes the watch. If you only have the case and movement without the bracelet... imho you only have half the watch.
Another great Ambassador with an original bracelet. This is a 1937 Bulova Ambassador. The 26.5% price difference between white and yellow gold might explain why the yellow gold models are much rarer during this period.

It's getting more and more difficult to find these still sporting the original band. Nice!
1937 Ambassador, all day by case s/n..
Can you verify arrow stamp on movement? In your photo to the left of "fifteen", it looks like a circle with a lighter crescent moon next to it. Might this be the movement photo from the other Ambassador you just posted?
In reply to It's getting more and more… by neetstuf-4-u
Oops.. you are right. I'll fix it soon. Pics at the same time.
Another fantastic example, congrats!
1937 Bulova Ambassador