The present watch is an extremely charismatic and rare example of an early GMT-Master model reference 6542. It features not only the original bakelite bezel in very good condition but also a highly charismatically aged brown lacquered dial with gold printing. Amongst collectors, this type of dial is now called "tropical". This designation is derived from the colour of the lacquer which over the years has changed from black to a warm chocolate brown. The watch is furthermore preserved in overall very good original condition.
Due to the extraordinary success of the Rolex Sports models in the 1950s, it came to no surprise when the world’s largest airline Pan Am commissioned a specially designed watch allowing their pilots to keep track of time in two locations.
With the beginning of transatlantic flights with jet aircrafts in 1956, travellers appreciated the fact that the journey times were reduced from 13 hours to 7 but suffered from new phenomena, the jet lag. Worried about the possible effects on their pilots and, after researches, Pan Am management advised them to keep on "home" time while away from base. As at the same time they needed to know the local time and consequently, a joint task force from Pan Am and Rolex was assigned. The team devised a watch with an additional hour hand, which revolved once every 24 hours and a rotating bezel marked with those same 24 hours. The model was named "“G.M.T.-Master" after the world's standard time, the Greenwich Mean Time.
The first GMT model, reference 6542, was launched in 1956 and was immediately recognizable by the bright acrylic or bakelite bezel insert with the twenty-four hour markings printed to its underside. This material was chosen to reduce reflection which would disturb the pilots. The bezel ring was also made of acrylic and coated in an alloy to resemble metal. It then turned out that the flexibility of this material could cause the bezel insert to break and that in very warm environments the printing would often flake off. Consequently, Rolex decided to replace the acrylic insert against a more resistant metal version. The dial of the first examples featured the designation "Swiss" below 6 o'clock, the numerals coated with phosphorescent (glow-in-the-dark) luminova. As of the late 1950s/early 1960s, the luminous material was changed to tritium, indicated by the "Swiss - T < 25" designation, the dial with all white print.
The present watch is fitted with a transitional dial, marked "Swiss - T < 25", the signature, model name and numerals printed in white while still retaining the five minute scale printed in gilt. It furthermore features the calibre 1066 movement, used for the late 1950s/early 1960s series of the GMT-Master.
The few examples of the early GMT Master series which have survived with the original bezel are highly sought after collector's watches.