The rotating bezel has always been a landmark feature in Rolex’s production line, as a constant aid to divers, pilots and other technical-related professionals. While the Turn-O-Graph ref. 6202 was the very first Rolex model to officially feature a rotating bezel, the reference ceased production after a few years due to its lack of popularity.

Rolex merged the ‘Turn-O-Graph’ with the ‘DateJust’ in 1954 with reference 6309. The model was advertised with images of the U.S. Air Force acrobatic flying team, or ‘Group Number 3600 of Air Demonstration’. Reference 6309 and its successors adopted the namesake ‘Thunderbird’ after the flying team’s emblem. The present watch, reference 1625, is a later reinterpretation of the original ‘Thunderbird’, featuring an updated case shape and movement caliber.
The model was not particularly commercially successful during its day, which makes it today extremely rare.

The present example sets itself apart from its peers due to an unusual detail. Normally, the model features luminous accents to the indexes (and luminous hands). But in this instance there is no trace of such accents, and the hands do not even have to groove to accomodate the radium. This is because in the late 1950s and early 1960s, some countries such as Canada and Japan banned radium due to health concerns. Consequently, before the luminous material was changed to tritium by the entirety of the market in circa 1963, specimens destined to these markets made before 1963 (such as this 1961 example) were made without luminous material.

An intriguing historical detail which amplifies the rarity and collectability of the present piece.