I found several ads on mybulova.com ((https://mybulova.com/sites/default/files/vintage_ads/bulova- d- 1938- .jpg;https://mybulova.com/sites/default/files/vintage_ads/1940-Bulova-ad-1.jpg) that seem to indicate that this is an American Clipper. The case is marked "B-10K ROLLED GOLD PLATE". The movemet is marked with an Omega although it is hard to see in the picture. The case is 25 mm wide, excluding crown and 36.5 mm long lug to lug. The lug width is 13 mm. The caseback is marked on the narrow, slanted edges, note on the larger case back. The crown is signed. I was wondering what the "B" indicated in the "B-10K ROLLED GOLD PLATE" labeling. Also, I know that watches were smaller in the 1930s and 1940s but I the ads make it look like the American Clipper could be either a mens or ladys watch. Were there two different sizes and if so I wonder which one my watch is. Thank you. Lking forward to your comments.
John




I've updated the year to 1938 as per the first number in the case serial number.
Black dial with yellow gold plain case would be a match for the 1938 Bulova American Clipper "C"
In reply to Nice one John - man's watch… by Geoff Baker