Sky-Dweller
THE ULTIMATE WATCH OF PRESTIGE
The Oyster Perpetual Day-Date is the most prestigious and most exclusive watch in the Oyster Perpetual collection.
At its launch in 1956, the Day-Date was a major innovation: it was the first calendar wristwatch to indicate, in addition to the date, the day of the week spelt out in full in a window on the dial – a technical feat at the time. The Day-Date has only ever been made from precious metals –18 ct yellow, white or Everose gold, or 950 platinum.
THE ‘PRESIDENTS’ WATCH’
Worn by many of the world’s political figures, directors and visionaries, the Day-Date is instantly recognizable, in particular thanks to its emblematic President bracelet, whose evocative name, together with the eminent figures who have worn it, ensured the Day-Date became known as the ‘presidents’ watch’.
INSTANTANEOUS DAY AND DATE
The Day-Date’s calendar displays the day of the week spelt out in full in an arc-shaped window at 12 o’clock in addition to the date in a separate window at 3 o’clock. This display relies on disc mechanisms; the day and date change simultaneously and instantaneously. The indication of the day of the week is available in a choice of 26 languages. The Day-Date is also equipped with a mechanism allowing rapid adjustment of the day and the date using the winding crown.
THE DAY-DATE, SUPERLATIVE CHRONOMETER CERTIFIED
Like all Rolex watches, the Day-Date is covered by the Superlative Chronometer certification redefined by Rolex in 2015. This exclusive designation testifies 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 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 Day-Date’s Oyster case, 36 or 40 mm in diameter and guaranteed waterproof to a depth of 100 metres (330 feet), is a paragon of robustness and elegance. The middle case is crafted from a solid block of 18 ct yellow, white or Everose gold, or 950 platinum. The case back, edged with fine fluting, is hermetically screwed down with a special tool that grants only certified Rolex watchmakers access to the movement. The Twinlock winding crown, fitted with a double waterproofness system, screws down securely against the case. The bezel can be fluted or set with diamonds. The date display at 3 o’clock is magnified by a Cyclops lens on the crystal, which 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 3255
The Day-Date 36 and Day-Date 40 are equipped with calibre 3255, 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 3255 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 3255 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 3255 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 a constant source of 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 Day-Date’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.
THE PRESIDENT BRACELET
Created specially for the Day-Date and unveiled in 1956 at the model’s launch, the elegant and imposing President bracelet is inherent to the standing of the watch. Immediately recognizable, this solid 18 ct gold or 950 platinum bracelet with three semi-circular links provides complete reliability and comfort.
The President bracelet is fitted with a concealed Crownclasp, developed by Rolex and patented, which opens with a hinged Rolex crown, providing a final aesthetic and functional touch. The bracelet includes ceramic inserts – designed by the brand and patented – inside the links to enhance its flexibility and longevity.