GMT-Master II
A HOMAGE TO AVIATION
The Oyster Perpetual Air-King celebrates the aeronautical heritage of the original Oyster.
The Air-King sports a distinctive black dial with a combination of large 3, 6 and 9 numerals marking the hours and a prominent minutes scale for optimal navigational time readings. Its case, with a diameter of 40 mm, is made of Oystersteel. Since 2022, it has included a crown guard and has straight sides like that of the other Professional category models – except for the Explorer 36 and Explorer 40.
The name ‘Air-King’ has featured on the dial since the watch’s launch in 1958, in lettering that makes the model easily identifiable. Rolex’s symbolic crown is displayed in yellow, while the seconds hand and the name ‘Rolex’ are green, echoing the brand’s emblematic colour.
A HOMAGE TO AVIATION
The Air-King symbolizes the privileged relationship between Rolex and flying during the golden age of aviation in the 1930s. It pays tribute to the pilots of the era and the role of the first Oyster watches in their epic story.
The 1930s saw spectacular progress in aircraft performance that constantly expanded humanity’s capacity to conquer the skies and led to the introduction of long-distance flights. Several pilots set records while wearing an Oyster watch. Others used the timepiece as an on-board chronometer. Among these airborne adventurers was the English aviator Charles Douglas Barnard. Of the Oyster, he said: “The peculiar qualities of this Rolex watch render it eminently suitable for flying purposes and I propose to use it on all my long-distance flights in the future.” In 1933, the brand’s watches accompanied the Houston Expedition as it made the first-ever flight over Mount Everest at an altitude exceeding 10,000 metres (33,000 feet) in extreme weather conditions. In 1934, when Owen Cathcart-Jones and Ken Waller made a return voyage from London (United Kingdom) to Melbourne (Australia) in record time with a twin-engine De Havilland Comet, an Oyster watch served as their on-board chronometer.
CHROMALIGHT DISPLAY
The Air-King offers great legibility in all circumstances, even in the dark, thanks to its Chromalight display: the 3, 6 and 9 numerals and the hands are filled or coated with a luminescent material emitting a long-lasting blue glow – for up to two times longer than traditional phosphorescent materials.
THE AIR-KING, SUPERLATIVE CHRONOMETER CERTIFIED
Like all Rolex watches, the Air-King is covered by the Superlative Chronometer certification redefined by Rolex in 2015. This exclusive designation attests that every watch leaving the brand’s workshops has successfully undergone a series of tests conducted by Rolex in its own laboratories and according to its own criteria. These certification tests apply to the fully assembled watch, after casing the movement, guaranteeing superlative performance on the wrist in terms of precision, power reserve, waterproofness and self-winding. The Superlative Chronometer status is symbolized by the green seal that comes with every Rolex watch and is coupled with an international five-year guarantee.
The precision of every movement – officially certified as a chronometer by the Swiss Official Chronometer Testing Institute (COSC) – is tested a second time by Rolex after being cased, to ensure that it meets criteria that are far stricter than those of the official certification. The precision of a Rolex Superlative Chronometer is of the order of −2/+2 seconds per day – the rate deviation tolerated by the brand for a finished watch is significantly smaller than that accepted by COSC for official certification of the movement alone.
The Superlative Chronometer certification testing is carried out after casing using state-of-the-art equipment specially developed by Rolex and according to an exclusive protocol that simulates the conditions in which a watch is actually worn and more closely represents real-life experience. The entirely automated series of tests also checks the waterproofness, the self-winding capacity and the power reserve of 100 per cent of Rolex watches. These tests systematically complement the qualification testing upstream during development and production, in order to ensure the watches’ reliability, robustness, and resistance to strong magnetic fields and to shocks.
THE OYSTER CASE, SYMBOL OF WATERPROOFNESS
The Air-King’s Oyster case, 40 mm in diameter and guaranteed waterproof to a depth of 100 metres (330 feet), is a paragon of robustness and reliability. The middle case is crafted from a solid block of Oystersteel. The case back, edged with fine fluting, is hermetically screwed down with a special tool that grants only Rolex watchmakers access to the movement. The Twinlock winding crown, fitted with a double waterproofness system and protected by an integral crown guard, screws down securely against the case. The crystal is made of virtually scratchproof sapphire and benefits from an anti-reflective coating. The waterproof Oyster case provides optimal protection for the movement it houses.
CALIBRE 3230
The Air-King is equipped with calibre 3230, a self-winding mechanical movement entirely developed and manufactured by Rolex. A consummate demonstration of technology, this movement carries a number of patents. It offers outstanding performance, particularly in terms of precision, power reserve, convenience and reliability.
Calibre 3230 incorporates the patented Chronergy escapement, made of nickel-phosphorus, which combines high energy efficiency with great dependability and is also resistant to strong magnetic fields.
The movement is fitted with the blue Parachrom hairspring, manufactured by Rolex in a paramagnetic alloy. In addition to resisting strong magnetic fields, this hairspring offers great stability in the face of temperature variations as well as high resistance to shocks. It is equipped with a Rolex overcoil, ensuring the calibre’s regularity in any position.
The oscillator of calibre 3230 has a large balance wheel with variable inertia regulated extremely precisely via gold Microstella nuts. It is held firmly in place by a height-adjustable traversing bridge enabling very stable positioning to increase shock resistance. The oscillator is also mounted on the Rolex-designed, patented high-performance Paraflex shock absorbers, further enhancing the movement’s shock resistance.
Calibre 3230 is equipped with a self-winding system via a Perpetual rotor, which ensures continuous winding of the mainspring by harnessing the movements of the wrist to provide constant energy. Its oscillating weight has been fitted with an optimized ball bearing since 2023. Thanks to its barrel architecture and the escapement’s superior efficiency, the power reserve of this movement extends to approximately 70 hours.
The Air-King’s movement will be seen only by certified Rolex watchmakers, yet it is beautifully finished and decorated. Since 2023, it has also been marked with the words ‘Chronometer Perpetual’ and ‘Superlative Adjusted’ engraved respectively on the oscillating weight and on the bridges.
BRACELET AND CLASP, SECURE AND COMFORTABLE
The Air-King is fitted on a three-piece link Oyster bracelet. This bracelet is equipped with the Rolex-designed, patented Oysterlock safety clasp, which prevents accidental opening. It features the Easylink comfort extension link, developed by the brand, which allows the wearer to easily increase the bracelet length by approximately 5 mm, for additional comfort in any circumstance.