A Dunhill Paris marked UG emerged at an AQ auction. Estimate was EUR 3.000-5.000 but not sold The link itself seems to be solid: Description: Fine and very rare 18K pink gold manual winding astronomic chronograph wristwatch with 3 registers. Day, date, month and moon phase. With Duhnill (sic) Paris engraved between the lugs at 6. 4 Further: Case No. 372829 In the caseback: 32.339. Also: movement marked with (US import) code HOX - which was indeed used by UG but not for import in France. So: weird numbers, non logic import code. Number inside caseback may be a Dunhill number. Number described as case number may simply be missing the 1 but unfortunately no pic of the outside of the cb.
Tavannes was another supplier for Dunhill (as well as for Cartier). They printed both names on the dial
Also V&C and Ulysse Nardin supplied watches. However: still no clue about the numbering and/or Dunhill inscriptions
Although I can’t speak to the watch in question, being a long time fan of Dunhill pipes, tobacco and smoking accoutrement (I have a very large hoard of tinned Dunhill from before they got out of the tobacco trade a few years ago and sold the brand to Peterson’s- Alfred would be horrified), everything they touched was absolute class.