Hi Erich, do you mean Seamaster? Mmmmmh this do not really help at mine is a Speedmaster...
Do you mean that early Seamaster, Railmaster and Speedmaster all had Naiad type crowns?
I have now heard that this extra logo might be a distinctive sign of omega sport watches exported to central and south America in the early 60's.
Does anyone know more about this?
In advance, thank you
Ztirual