Rolex GMT-Master

A pilot's watch with an extra hand and a two-coloured bezel for reading two time zones at once.

Rolex developed the GMT-Master for Pan Am pilots on long flights between time zones. The red and blue bezel shows day and night in the second time zone. The GMT-Master II of 1983 allowed the hour hand to be set independently.

Materials: Stainless steel, bezel in Bakelite and later aluminium or ceramic; self-winding movement

Manufacture: Made in Geneva; the movement has a fourth hand that turns once in 24 hours.

The red and blue bezel for day and night.

The extra hand with a triangle at its tip.

The first reference, 6542, appeared in 1954 with a Bakelite bezel. The Bakelite cracked easily and was painted with luminous radium, and it was soon replaced by metal.

An extra hand goes round the dial once in 24 hours and points to the bezel’s 24-hour scale. If the bezel is turned, the hand shows the time in another time zone.

An arrow-shaped fourth hand and a two-colour bezel, most often red and blue (known as the Pepsi) or black and blue.

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