Early chronometer certification
I own a 1960 Rolex 5512 Submariner -It is a 1560 caliber chronometer.
Since the COSC was formed in 1973-74 for Swiss watch movement certification, what was the certification method that Rolex used for its "officially certified"
or superlative chronometers prior to COSC?
Was it in-house at the Swiss factory or did Rolex out-source the movement testing and certification?
|