Early Chronographs (pre-Daytona) Jean-Claude Killy 4767

The first Oyster Dato-Compax (1947): Rolex’s first water-resistantWater resistanceA watch’s ability to resist water entering its case under specified conditions, often stated as a pressure or equivalent depth. Seals can deteriorate and the crown can be damaged, so an original rating does not establish a vintage watch’s present resistance. chronographChronographA watch function for starting, stopping and resetting an elapsed-time measurement independently of the ordinary time display. with triple calendar, day and month in windows under twelve and the date on a blue outer scale read by a central hand.