Hi,
Does anyone have any idea watch the OXG engraving on an Omega Speedmaster cal. 321 means?
It's on the left next to the screw that is next to the 321 engraving.
Thanks,
Bernard

 

Some bread crumbs worth following.

https://omegaforums.net/threads/speedmasters-with-adjusted-caliber-321-movements.51696/

 

OXG is the import code for Omega watches or uncased movements delivered to the USA.

 

Correct. This is what I turned up a few years ago inquiring on WUS, and, some time after that, I acquired a 105.012-66CB with both "UNADJUSTED" and OXG markings on the movement. A subsequent Omega archive extract confirms original delivery to United States.