Zenith Unites with Kari Voutilainen & Phillips to Revive The Brand’s Prestigious Calibre 135-O Movement

When talking about the Calibre 135, the first thing you need to know is that it is truly an icon because its qualities are unequaled.

Developed by Swiss watchmaker Ephrem Jobin in 1945, the Calibre 135 was designed with a rather large 14mm balance wheel to enhance precision and rate stability that was powered by a massive barrel which consistently maintained the regulator. Once it went into production, from 1949 to 1962, two versions of the calibre were ultimately made. The first, which lacked the “O” designation, was a commercial version that went into approximately 11,000 watches.
 

However, beyond the commercial version, there existed another variant of this movement, the Calibre 135-O, made solely for taking part in chronometry competitions at the Observatories of Neuchâtel, Geneva, Kew Teddington, and Besançon. And it was this calibre (where “O” stands for “Observatoire”) that won more observatory chronometer awards than any other movement in the history of watchmaking – including a five-year winning streak – and bolstering Zenith’s reputation as an undisputed leader in precision chronometry.
 

Speaking about the brand’s history, Julien Tornare, CEO of Zenith, said, “Yes, those calibres are part of the heritage, and we will keep some of them in our museum. But together, with Phillips, we challenged each other, wondering how we could give a better tribute to the founders, the people who made this movement, and the people who were regulating this famous calibre.”
 

That was how the idea of a special series built around the Calibre 135-O was born, and ten movements from 1950 to 1954 (the height of Zenith’s competition-winning period) were carefully selected and cased for this remarkable collaboration.

But after Zenith and Phillips somehow found a vehicle for giving the chosen calibres new life, Alexandre Ghotbi, Head of Watches at Phillips for Continental Europe & the Middle East, couldn’t help but wonder: “These calibres were made for competitions. They were not made to be worn or to be aesthetically pleasing. So, if we’re going to make a wristwatch out of this legendary calibre, who should we ask to take it to the next level?”
 

Immediately, the name of Kari Voutilainen was put on the short list. And, frankly speaking, no one else was seriously considered.

Thanks to Kari Voutilainen, for the first time in the history of the Calibre 135-O, the observatory chronometer movement has impeccable decoration and finishing. But it was very difficult work because, when doing this type of restoration, you have to do everything in one go.
 

While restoring and decorating the movements, Kari Voutilainen was careful to preserve the original regulation and fine-tuning of the calibres by celebrated Zenith chronométriers Charles Fleck and René Gygax, explaining: “The persons working on these movements were the best watchmakers at the time. They had the know-how to make things precise. That precision doesn’t disappear after 70 years. Our duty was not to touch that performance.”