I bought an what I believe to be 23.4 omega from 1940's. However there is a letter M on the movement and I can't find any reference on what it means. Maybe someone from this forum can shed the light on this. Thanks in advance.
Can you show a shot of the whole movement? But generally it denotes the country it went too, I believe.
It means Metal. This movement was supposed to be in watch in a not precious metal, like stainless steel, and not gold.
Can someone confirm that this is in fact cal 23.4. It looks correct but I think there were other similar calibers. Thanks
The shape of the train bridge is like the larger caliber 30s so it fits in between the 19.4 calibers and the 23.7 family which used the larger train bridges. A 23.4 SC, as used in Omega's first centre seconds watch, the Medicus.