The round counterweight on the seconds hand is now the same width of the arrow on the other end, where it had once been larger. The words “J12” and “Automatic” were changed to the official Chanel font, and the Arabic hour numerals have been reworked by a professional typographer. The old numerals looked good on the wrist, but they had flat portions on their curves that became glaring when enlarged—like on an ad, for example. The numerals are also now made out of ceramic.
 
All these changes were just for the dial alone. On top of the dial changes, the team also modified the proportions of the bracelet, making the links longer and narrower to make the design more contemporary. On the bezel, there are now 40 notches on the outer rim where there were once just 30. The indentations on the underside of the bezel were also changed, so that turning the bezel would result in a pleasant sound—Beau likened it to the sound of the door closing on a luxury sports car in comparison to that on a normal car. When you are Chanel, these details matter.

(Related: Here's How Chanel Celebrated The Arrival Of The New J12 Watch In Paris)

The final changes were made to the back of the watch. Beau said frankly, “The one flaw in the previous J12 was that it was not as beautiful to view from the back as it was from the front.” It was no easy problem to remedy, as the steel caseback of the old J12 housed a conventional ETA movement, procured from the Swatch Group, that Beau confessed was “not necessarily beautiful”. He said, “Not that [an] ETA [movement] is bad, but we thought a luxury brand like Chanel deserves something of a higher level.” To achieve this, Chanel entered a partnership with an unexpected party—the Hans Wilsdorf Foundation, of Rolex and Tudor fame.

For Beau, the rationale was simple. “We wanted a partner that was secretive, that was not for sale, and that had the same values of luxury as Chanel.” The partnership resulted in Kenissi, a company originally started to make movements for Tudor. Today, Chanel owns a 20 per cent stake in Kenissi, and the J12 has a completely new self‑winding calibre specially developed just for the watch. It includes a beautiful oscillating weight with a circle motif cut out of its centre—Chanel’s watchmaking signature—which necessitated that it be made out of tungsten to maintain winding efficiency. It is visible through a new sapphire glass caseback, which is anchored to a new ceramic caseback plate. The new calibre, called 12.1, is chronometer-certified by the Swiss Chronometer Testing Institute (COSC) for optimal precision and reliability.

The J12 became an overnight sensation when it was first introduced in 1999 by Jacques Helleu, then-artistic director of Chanel. To edit such an icon, as the Chanel team had to, was difficult. To contemporise the J12 while still respecting the spirit of Helleu’s work was also no easy task, and the team approached it with the precision of a plastic surgeon. Some 70 per cent of all components were changed in total, but the new J12 looks just like a slightly refreshed version of its iconic self, which is precisely what Chanel would have wanted.