The Rolex Cosmograph Daytona reference 6239 was launched in 1963 as the first Cosmograph in the brand’s collection, replacing reference 6234. Phillips catalogues stainless steel examples at 36.5 mm, fitted with plain non-screw-down pushers and an engraved steel bezel carrying the tachymeter scale, a change that freed the dial of the scale and made it easier for racing drivers to read. Inside is a manual-wind chronograph movement based on the Valjoux 72, reworked by Rolex as calibre 72B and later 722, beating at 18,000 vibrations per hour, with 17 jewels on the Phillips example. Phillips describes its black dial with silver sub-dials as the earliest Cosmograph with that combination. The model matters because it founded the Daytona line, today one of the most recognised chronographs in the world.

The name comes from Daytona Beach and its racing history; Rolex had become official timekeeper of Daytona International Speedway in 1962. According to the Phillips catalogue, the earliest 6239s, starting around serial 922,900, had no Daytona signature at all, and the model was briefly known as the “Le Mans”. When the word did appear, it was printed in a small script beneath “Cosmograph”, which collectors call the “floating” Daytona. Earlier examples also carry extra tachymeter graduations at 275 units. The 6239 is the earliest reference found with the exotic three-colour dial with block markers and crosshair sub-dials later nicknamed the “Paul Newman”.

The 6239 is one of the most important vintage chronographs for collectors. Its fame peaked in October 2017 when Paul Newman’s own 6239 sold at Phillips in New York for $17,752,500, at the time a record for a wristwatch. Ordinary examples are far more accessible: Phillips sold a floating Daytona with a black and silver dial for CHF 43,750 and a 1964 example for CHF 62,500, both above their CHF 30,000 to 50,000 estimates. Collectors pay close attention to originality of dials, bezels and pushers, since early variants differ in small details. The reference 6239 is no longer produced. Rolex still makes the Cosmograph Daytona, now a 40 mm automatic with calibre 4131 and a 72-hour power reserve.