Zenith calibre 135

The Zenith Chronometer Cal. 135, a remarkable creation from Zenith, was introduced in 1948 after being developed by Ephrem Jobin. While Zenith is widely known for the El Primero movement, the Cal. 135 stands out as a significant yet less renowned achievement. The movement came in two versions: the commercial 135 and the 135-O, the latter being used exclusively for chronometry competitions at observatories like Neuchâtel and Geneva. The 135-O won over 230 awards, making it the most awarded chronometer in watchmaking history.

In June 2022, Zenith, in collaboration with Phillips and renowned watchmaker Kari Voutilainen, revived the Cal. 135-O. This limited edition, known as the Cal. 135 Observatoire, features restored and decorated historical movements. The 38mm platinum case houses a black dial with a guilloché pattern, reflecting a blend of vintage elegance and modern craftsmanship. This edition was limited to 10 pieces, each meticulously finished by Voutilainen, highlighting the movement's historical significance and precision

This Zenith Cal. 135 is in very good condition. The case is well-preserved with minor signs of wear on the caseback. The movement is clean, functioning well, and keeps accurate time, with all caseback engravings, including the serial number, remaining deep and clear. The dial shows no signs of aging. It comes with a generic leather strap and buckle and is in full working order.