Another important point that characterizes this reference: because of its wider bezel, Rolex had to duplicate the Swiss mention which is at 6 o’clock in order to make it more visible on the dial. In reality, if we look closely, we see that the word Swiss was printed twice a few millimeters apart (invisible in the Sotheby’s photos).
As for the term Underline, it obviously concerns the line that is under the mention Cosmograph. We do not know with certainty the meaning of this line which appeared at the time on other models from Rolex… Some specialists believe that it would mean the passage of Rolex from radium to tritium.
As Le Mans celebrates its hundredth anniversary this year and as the Daytona celebrates its 60th anniversary, it was interesting to come back to reference 6239 “Le Mans” – you can see this name on old Rolex advertisements from the time.
As soon as the new Cosmograph model was released in 1964, Rolex added the inscription “Daytona” on the dial for the English-speaking market, in order to recall Rolex’s partnership with the American circuit.