The launch of reference 6240 ushered a new era for Rolex. The model’s historical importance cannot be overstated. In addition to the Oyster crown, the Cosmograph Daytona now showcased water resistant screw down pushers that would forever be part of Rolex’s legacy.

This reference 6240 is yet another variant of the diverse model. Instead of bearing the ‘Oyster’ designation, the dial displays ‘Rolex Cosmograph’ with ‘Daytona’ suspended below in a smaller size. As this timepiece shares the same dial configuration with the ‘Floating Dial’ reference 6239, one can conclude that Rolex used existing dials while testing out its new and innovative ‘Oyster’ chronograph model. Furthermore, the dial has toned down from black to a dark grey tone.

This example is fitted with a Mk 1 bezel and the chronograph buttons are original to the reference 6240. Having aged over time, the brass now peeks through the pushers. Featuring flat and fine grooves, they are referred to by collectors as ‘millerighe’. Later Daytona models would display much deeper grooves allowing for a firmer grip. Of particular note are the 71 end links, which are particularly coveted by collectors today.