I have a Universal Geneve wrist watch that has had me puzzled until lately when I was able to get a person at Universal to pin down the model and year of manufacture for me. On the face, it has the model name of "Contax". That was the puzzling part since all of my research only came up with "Compax" models, until my contact told me that in 1935 Universal originated this watch under the Contax model name but then changed it in 1936 to Compax which they have used ever since.
The case is 18k and is hallmarked on the side opposite the stem. The movement is a 285 and inside the back cover it is engraved with a model number 5922 and serial number 633211.
I don't think "Contax" is going to add value vs "Compax" if that is what you're after. It is however, a nice watch, and an 18k Compax/Contax usually trade in the $1500-1900 range.