A CHRONOGRAPH MADE FOR THE ROAD
The Cosmograph Daytona was designed to be the ultimate timing tool thanks to its precision and reliability. The watch, which is equipped with an additional mechanism to measure intervals of time displayed by secondary hands, also offers outstanding legibility of its functions. The time measurements are indicated clearly: the seconds are counted by the chronograph centre seconds hand, while the counters at 3 o’clock and 9 o’clock indicate the elapsed time in minutes and hours, respectively.

MEASURING SPEED UP TO 400 UNITS PER HOUR
The Cosmograph Daytona’s bezel, in gold or high-tech ceramic, functions as a tachymeter: its scale can be used to read an average speed over a given distance based on elapsed time. This scale, which offers optimal legibility, makes this chronograph the ideal instrument for measuring speeds up to 400 units per hour, expressed in kilometres, miles, or any other unit of measure.

THE OYSTER CASE, SYMBOL OF WATERPROOFNESS
The Cosmograph Daytona’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, 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 employed by approved watchmakers. The Triplock winding crown, fitted with a triple waterproofness system and protected by an integral crown guard, screws down securely against the case, as do the chronograph pushers. 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.

Since 2023, versions of the Cosmograph Daytona in 950 platinum have featured a transparent case back in sapphire crystal with an anti-reflective coating, offering the opportunity to admire the decorations on the movement and the pivoting of the oscillating weight.

BRACELET AND CLASP: SECURE AND COMFORTABLE
The Cosmograph Daytona is fitted with either a three-piece link Oyster bracelet or an Oysterflex bracelet, composed of two flexible, curved metal blades – one for each bracelet section – overmoulded with high-performance black elastomer. Both bracelets are equipped with a Rolex-designed Oysterlock safety clasp that prevents accidental opening.

The Cosmograph Daytona’s Oyster bracelet is fitted with the Easylink comfort extension link, developed by Rolex, which allows the wearer to easily increase its length by approximately 5 mm, for additional comfort in any circumstance. On the versions in 18 ct gold or 950 platinum, the Oyster bracelet includes ceramic inserts – designed by the brand and patented – around the pins inside the links to help prevent premature wear and to enhance its flexibility on the wrist.

The patented Oysterflex bracelet, developed by Rolex, is furnished with the Rolex Glidelock extension system, also developed by the brand and patented. On the Oysterflex bracelet, this inventive toothed mechanism has six notches of approximately 2.5 mm, allowing the bracelet length to be effortlessly adjusted up to some 15 mm.

CALIBRE 4131
The Cosmograph Daytona is equipped with calibre 4131, a self-winding mechanical chronograph movement entirely developed and manufactured by Rolex. A distillation of technology, this movement offers outstanding performance, particularly in terms of precision, power reserve, convenience and reliability. It incorporates a chronograph function with a reduced number of components, thereby further enhancing the movement’s reliability. The chronograph is engaged by a robust mechanism with a column wheel and vertical clutch. This enables an instantaneous and extremely precise start to the timing.

Calibre 4131 incorporates the patented Chronergy escapement, made of nickel-phosphorus, which combines high energy efficiency with great dependability and is resistant to strong magnetic fields.

The movement is additionally fitted with the blue Parachrom hairspring. Manufactured in a paramagnetic alloy enabling it to withstand strong magnetic fields, this hairspring also 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 4131 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, high-performance Paraflex shock absorbers, further enhancing the movement’s shock resistance.

Calibre 4131 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, which is cut out, is made of yellow gold on versions of the Cosmograph Daytona in 950 platinum. Thanks to its barrel architecture and the escapement’s superior efficiency, the power reserve of this movement extends to approximately 72 hours.

The Cosmograph Daytona’s movement is beautifully finished and decorated. In particular, its bridges are embellished with Rolex Côtes de Genève, an exclusive decoration that differs from the traditional Côtes de Genève by the addition of a slight polished groove between each band. Calibre 4131 is also marked with the words ‘Chronometer Perpetual’ and ‘Superlative Adjusted’ engraved on the oscillating weight and on the bridges, respectively. On the 950 platinum versions of the Cosmograph Daytona, it is visible to the wearer through the transparent case back.

THE COSMOGRAPH DAYTONA, SUPERLATIVE CHRONOMETER CERTIFIED
Like all Rolex watches, the Cosmograph Daytona is covered by the Superlative Chronometer certification. Symbolized by a green seal, this in-house certification is strictly controlled by internationally recognized, independent Swiss entities. It ensures the excellent on-the-wrist performance of each of the brand’s watches and is coupled with an international five-year guarantee.

In 2026, the Superlative Chronometer certification was expanded to seven testing criteria. Resistance to magnetism, reliability and durability were added to the criteria for precision, waterproofness, self-winding and autonomy, established when the certification was redefined in 2015.

The requirements in terms of precision are particularly stringent. Each Rolex movement is first officially certified as a chronometer. This means that, having passed a series of eliminating tests, it fulfils the criteria governing the ‘chronometer’ designation for wristwatches. For the category of calibres concerned, which includes all Rolex movements, the tolerated rate deviation is –4 and +6 seconds per day.

After casing the movement, the precision is then tested again, following a protocol developed by Rolex that simulates real-life wearing conditions, to meet even stricter criteria: the watch’s accuracy must be between –2 and +2 seconds per day. The rate deviation tolerated by the brand for a finished watch is therefore significantly smaller than that accepted for official certification of the movement alone.