The ref. 16520 was the first Cosmograph Daytona to run on a self-winding movement, which was manufactured by Zenith. Also referred to as the “El Primero”, the calibre 4030 is a unique movement within the Rolex catalog. Minor details along the bezel can help determine the era of a Zenith Daytona.
The 200 bezel was used in 1988 and early 1999, then graduated from 50 to 200. These bezels were similar to the bezels used on the manual-wind Daytonas, with the ?UNITS PER HOUR? text at three o?clock. The version displayed here has the text at one o?clock and was graduated up to 400.
The model saw several other developments, mainly consisting of the layout of the dial. In fact, five different changes have been identified, and the present lot is part of the third iteration distinguished by the five lines of text and the “inverted 6” within the hours chronograph counter.
As of the year 2000 Rolex discontinued the ?Zenith Daytona? and introduces the 1165xx collection with the in-house movement, the Calibre 4130. At first glance, the two generations of the automatic Daytona look the same with similar design blueprints. However, upon closer inspection, the Daytona dial reveals which movement lies inside the watch. The order of the sub-dials is what distinguishes the Zenith Daytona from the in-house Daytona. On the Zenith Daytona watches, the 30-minute counter is located at 3 o?clock, the 12-hour counter is located at 6 o?clock, and the running seconds is located at 9 o?clock. On the in-house Caliber 4130 Daytona watches, the running seconds is located at 6 o?clock and the 12-hour counter is located at 9 o?clock ? those two sub-dials switched positions while the 30-minute counter remained in its original location.
Dimension
Fits a wrist size of 7 inches or smaller.
















