Born in the Cockpit: The Pan Am Origins

The Rolex GMT-Master was born from a specific, practical need. In the early 1950s, Pan American World Airways approached Rolex to develop a watch that would allow pilots to track two time zones simultaneously. Jet travel was making the world smaller, and pilots crossing multiple time zones needed a reliable instrument on their wrists.

Rolex responded with the ref. 6542 in 1955, featuring a 24-hour graduated bezel and an additional GMT hand that completed one full rotation every 24 hours. The original bezel was made of Bakelite in a distinctive blue and red colour scheme. That colour combination would become the most iconic bezel in watchmaking history.

The Colour Codes: Understanding GMT Bezel Nicknames

Rolex has never officially endorsed the collector nicknames for its GMT bezels, but these names have become the universal language of the market:

Pepsi (Blue/Red)

The original colourway, dating back to the first GMT-Master. The blue represents daytime hours, the red represents nighttime hours on the 24-hour scale. The "Pepsi" nickname is decades old and universally recognized. In its current ceramic form on the ref. 126710BLRO, it is arguably the most desirable colour combination in Rolex's entire lineup.

Batman / Batgirl (Blue/Black)

Introduced in 2013 on the ref. 116710BLNR, the blue and black bezel was the first two-tone Cerachrom ceramic bezel Rolex produced. On an Oyster bracelet, it is known as the "Batman." When Rolex moved the BLNR designation to the jubilee bracelet (ref. 126710BLNR), collectors dubbed it the "Batgirl," though many simply call both variants "Batman."

Root Beer (Brown/Black or Brown/Gold)

The Root Beer nickname applies to warm-toned GMT bezels, traditionally found on two-tone or solid gold models. The ref. 126711CHNR, in Everose gold and steel, features a brown and black ceramic bezel that has earned a devoted following among collectors who prefer something less flashy than the Pepsi but more characterful than a monochrome bezel.

Coke (Red/Black)

The red and black bezel appeared on several vintage references, including the ref. 16710. It has not yet appeared in Cerachrom ceramic, making the vintage "Coke" GMT a collector's item with no modern equivalent.

Key References Through the Decades

The GMT-Master lineage breaks into two major branches: the original GMT-Master (single reference number series) and the GMT-Master II, which added the ability to independently set the local hour hand.

• Ref. 6542 (1955-1959): The original, with its Bakelite bezel. Extremely rare and valuable.
• Ref. 1675 (1959-1980): The long-running classic, available in Pepsi and various other bezel configurations. Crown guards were added during this production run.
• Ref. 16750 (1981-1988): Introduced a sapphire crystal and quickset date. Transitional reference.
• Ref. 16710 (1989-2007): The last GMT-Master II without a ceramic bezel. Available in Pepsi, Coke, and all-black. Powered by the calibre 3185, later 3186. Highly collectible.
• Ref. 116710 (2007-2019): First ceramic bezel GMT-Master II. Initially only in all-black (116710LN), later joined by the Batman (116710BLNR).
• Ref. 126710 (2018-present): Current generation, powered by the calibre 3285 with a 70-hour power reserve. Available in Pepsi (BLRO), Batman/Batgirl (BLNR), and other configurations.

The Jubilee Bracelet Revolution

When Rolex debuted the ref. 126710BLRO Pepsi on a jubilee bracelet in 2018, it was a polarizing choice. The GMT-Master had always been associated with the sportier Oyster bracelet. But Rolex was reaching back to the 1950s: the original ref. 6542 was occasionally delivered on a jubilee.

The market responded with overwhelming enthusiasm. The jubilee bracelet softened the GMT-Master II's tool-watch edges and gave it a dressier character. It quickly became the preferred configuration for most buyers, though Rolex later made Oyster bracelet versions available as well, giving collectors a genuine choice.

How the GMT Function Works

The GMT complication is one of the most practical in all of watchmaking, and the GMT-Master II's implementation is particularly elegant:

• The standard hour and minute hands display local time, exactly like any other watch.
• The arrow-tipped GMT hand points to a second time zone on the 24-hour graduated bezel. This hand completes one revolution every 24 hours, eliminating AM/PM confusion.
• On the GMT-Master II (as opposed to the original GMT-Master), the local hour hand can be independently adjusted in one-hour jumps without stopping the movement. This means you can change time zones by adjusting the hour hand without resetting the minutes and seconds.
• By rotating the bezel, you can track a third time zone using the GMT hand as a reference.

For Canadian travellers crossing between Eastern, Central, Mountain, and Pacific time zones, the GMT function is genuinely useful rather than merely ornamental.

Explore Our GMT-Master II Collection

The Rolex GMT-Master II is a watch designed for people who move through the world. Its dual-time-zone functionality is backed by seven decades of refinement, and its bezel colour combinations have created some of the most recognizable watches on the planet.

Browse our GMT-Master II inventory to find your preferred reference and colourway. Whether you're drawn to the heritage of a Pepsi, the modernity of a Batman, or the warmth of a Root Beer, Watches Established has authenticated examples ready to ship across Canada.