GMT-Master

The GMT-Master was born in 1954 with reference 6542, developed in response to a very concrete need of the airline Pan American Airways: its pilots, flying increasingly long intercontinental routes as long-range aircraft came into service, needed a watch able to read local time and a second reference time zone simultaneously, typically Greenwich Mean Time, from which the model takes its name. Rolex's technical solution was a fourth central hand, calibrated over a 24-hour revolution and mechanically linked to the hour hand, which allows the second time zone to be read thanks to a rotating bezel also graduated over 24 hours.

The blue-and-red two-colour bezel of the 6542, designed to distinguish daytime from night-time hours at a glance, became over time so closely associated with the model that it earned the popular nickname "Pepsi," for its chromatic resemblance to the soft drink's logo. The 6542 was followed over the decades by references 1675 (1959-1980) and 16750 (1980-1988), which progressively refined the movement and case robustness while keeping the original functional layout intact.

1982 marked a turning point with the introduction of the GMT-Master II, reference 16760: unlike the original GMT-Master, the new version allowed the hour hand to be set independently of the GMT hand, making it easier to change time zone while travelling without having to stop the watch. The 16760 also introduced the first black-and-red two-colour bezel for a Rolex GMT. The "original" GMT-Master and the GMT-Master II coexisted in the catalogue for a few years, until, in the 2000s, the "II" designation was retained as the line's sole name. The most recent versions, starting with reference 116710LN from 2005-2007, adopted the single-colour or two-colour Cerachrom ceramic bezel, more resistant to scratching and fading than the previous aluminium inserts.