Very nice Executive Constantin!
And how are your Westfields? :-)
Edit-sorry, Senator not Executive.
This one has caught us out before. The case is not a match for the Senator. Looking now.
The later 1928 Senator has a case match but the side engraving differs.
The only other case shape match I can find is the ladies sports 'Wimbledon' from 1929, which may be correct as the engraving on the back of the watch is a womens name.
The Wimbledon is smaller, 30.2 X 21mm, and holds a 8''' movement.
The Senator is 33 X 26.5mm. The bezel engraving is not a match either.
The Senator ads that match the engraving on this case has straight through lugs/engraving, whereas the subject has not only "bevelled" engraving, but the lugs are also fatter/wider than the bezel.
No match found, and both of the other Senators in the DB are the same as this one, therefore we have no definite Senator examples onsite. This means we either call this a Senator too (rightly or wrongly), or rename all others as "unknown".
Here is Jaroslav's excellent mockup, showing in detail all similar models, none of which match.
Bobbee, where did these numbers come from and what evidnece do you have that the Wimbledon was only ever released with a size 8 movement?
How do you explain the female name engraved on the back indicating that its a ladies watch. 10AN were certainly used in ladies watches of this era.
This is Lisa's example. She gives all dimensions and a matching ad.
Engraving only means it coyld be à gift from a sweetheart, or a woman wore a man's watch, nothing more. It in no way indicates it is a ladies size watch.
Some women in the "Roaring Twenties" also wore men's suits, slicked back their hair, and generally cultivated the androgynous look. Wearing a mans watch is just another affectation.
The watch(es) look like the earlier Senator case with the later December 1926 engraving.
It could be an "interim" style, or another model, we don't know.
As watch is dated on the movement and case 1927 and we do not have a advert match I'm also with Unknown.
Wonderful watch, even the crown looks original, I like this one a lot. We've discussed this style several times, still Unknown to me......