The Rolex Day-Date 40 marks the update for what officially is called the Oyster Perpetual Day-Date, featuring “a modernized design with a 40mm case” and a new movement, caliber 3255. The Rolex Day-Date 40 will be available exclusively in 950 platinum, 18k yellow, white or Everose gold. Size-wise, this new version replaces the Rolex 41 mm Day-Date II (reviewed here) exactly matching the diameter of the brand’s sportier watches such as the Submariner, Daytona, GMT-Master II.

The Rolex Day-Date 40 features a range of new dials with thin, laser-etched motifs, applied over a traditional sun-ray finish. Seen above is the version with the “deconstructed Roman numerals,” with numerous hand-applied pieces making up the individual numerals. The laser etching appears to be as sharp and and defined as one would expect to see from Rolex, but if you want one of these new unique dials, you will have to get the Rolex Day-Date 40 as they are exclusive to this release.

Rolex claims the new movement, 3255, establishes a new standard for superlative precision and they indeed back that statement up with some figures and proper testing: the new movement (followed up by the also new caliber 2236 that will find its way into the Lady-Datejust) is twice as exacting as those for a chronometer officially certified by COSC. The big deal is that Rolex has developed new, “high-technology methodology and equipment to test the precision of its Superlative Chronometers.”

What happens is that Rolex will continue to subject all its uncased movements to official COSC certification tests and, on these new movements, the assembled watches will be tested in-house by Rolex, for the twice as stringent -2 / +3 precision the new calibers have been designed to maintain. So how is this extreme precision achieved and maintained?

The new movement boasts 14 patents, which, all together, account for the gains in precision, power reserve, shock resistance, and magnetism. It incorporates the new Chronergy escapement – patented, of course – with pallet fork and escape wheel made of anti-magnetic nickel-phosphorus. The oscillator has an optimized blue Parachrom hairspring – which, interestingly, is not Rolex’s new Syloxi silicon hairspring that was debuted more quietly last year. Parachrom is made from an exclusive-to-Rolex para-magnetic alloy – with no further information being given on what that contains. The point is that it is said to be 10 times more precise and it certainly accounts for the highly enhanced and reliable accuracy of the new Rolex 3255 caliber. The movement, with bi-directional automatic winding, features an upped power reserve, reaching 70 hours now.

The trademark gold or platinum “President bracelet” has also been updated with ceramic inserts inside the links in an effort to enhance suppleness and durability. How these inserts have actually been implemented is something we will see very soon, when going hands-on with this new release. The Crownclasp is opened with a hinged Rolex crown and is expected to be slightly thinner and even more comfortable.

The Rolex Day-Date 40 is available in 950 platinum (Reference 228206), 18k Everose gold (Reference 228235), 18k yellow gold (Reference 228238), and 18k white gold (Reference 228239). Prices will be CHF59,600 Rolex Day-Date 40 Platinum, CHF35,800 for the Rolex Day-Date 40 Everose, CHF33,200 for the Rolex Day-Date 40 in yellow gold, and CHF35,800 for the white gold Rolex Day-Date 40. Look for a hands-on coming very soon. rolex.com

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