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THE COSMOGRAPH DAYTONA, SUPERLATIVE CHRONOMETER CERTIFIED
Like all Rolex watches, the Cosmograph Daytona 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 methodology 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 magnetic fields and shocks.
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, a particularly corrosion-resistant alloy, 18 ct 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 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. The waterproof Oyster case provides optimum protection for the Cosmograph Daytona’s movement.
PERPETUAL CALIBRE 4130
The Cosmograph Daytona is equipped with calibre 4130, a self-winding mechanical chronograph movement entirely developed and manufactured by Rolex. The architecture, manufacturing and innovative features of this movement make it exceptionally precise and reliable. A consummate demonstration of Rolex technology, the movement incorporates a chronograph function with a reduced number of components, thereby further enhancing its reliability. The chronograph is engaged by a mechanism with a column wheel and vertical clutch. This enables an instantaneous and extremely precise start to the timing.
The oscillator of calibre 4130 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.
Calibre 4130 has a blue Parachrom hairspring, manufactured by Rolex in a paramagnetic alloy. Insensitive to magnetic fields, the Parachrom hairspring offers great stability in the face of temperature variations and remains up to 10 times more precise than a traditional hairspring in case of shocks. It is equipped with a Rolex overcoil, ensuring its regularity in any position.
Calibre 4130 is fitted with a self-winding module featuring a Perpetual rotor, which ensures continuous winding of the mainspring by harnessing the movements of the wrist to provide constant energy. It offers a power reserve of approximately 72 hours.
The Cosmograph Daytona’s movement will be seen only by certified Rolex watchmakers, yet it is beautifully finished and decorated in keeping with the brand’s uncompromising quality standards.
BRACELET AND CLASP: SECURE AND COMFORTABLE
Depending on the version, the Cosmograph Daytona is fitted with either a three-piece link Oyster bracelet, or with an Oysterflex bracelet, both of which are equipped with a Rolex-designed and -patented Oysterlock safety clasp that prevents accidental opening. These bracelets are additionally fitted with 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.
The Cosmograph Daytona’s Oyster bracelet benefits from a concealed attachment system, ensuring seamless visual continuity between the bracelet and case. On the 18 ct Everose gold and 950 platinum versions, it includes ceramic inserts inside the links to enhance its flexibility and longevity.
Developed and patented by Rolex, the Oysterflex bracelet singularly combines the robustness and reliability of a metal bracelet with the suppleness, comfort and aesthetics of an elastomer strap. This innovative bracelet is made up of two flexible metal blades – one for each of the sections – overmoulded with black high-performance elastomer.