Zenith Chronometer

Zenith (Cal. 135) | Chronometer

ZENITH (CAL. 135) Chronometer. Type of watch: Wristwatch. Origin: Switzerland, Le Locle. Date: 1951. Clockwork: Manual winding, Cal. 135. Case/Wristband: Steel, leather strap with pin buckle, silver dial, hands and indices. Total Weight: ca. 40,5 g. Measurement: Ø 36 mm, length 21 cm. Case-No: 9175098. Movement-No.: 4251238. Description: 3-hand-wristwatch with subsidiary seconds at "6" o'clock. The Zenith Calibre 135 is considered one of the most outstanding clockworks in the history of watchmaking. Designed by Ephrem Jobin, one of the most famous watchmakers of his time, the calibre 135 was a milestone in the development of precision watch clockworks. With a diameter of 30 mm, it was larger than many of the clockworks commonly used at the time and thus enabled a larger balance and more stable oscillation behaviour. The calibre 135 was a hand-wound clockwork with a frequency of 18,000 vibrations per hour (A/h) and a power reserve of around 40 hours. Particularly noteworthy was the large balance wheel, whose inertia ensured exceptional stability and accuracy. Together with the screw balance and the fine adjustment, the clockwork was capable of impressive chronometric performance. Between 1950 and 1967, the calibre 135 won no fewer than 230 prizes in the chronometer tests of the Neuchâtel Observatory - an unprecedented achievement in the history of watchmaking. During this period, variants of the calibre were further refined specifically for competitions, reinforcing Zenith's status as a leading manufacturer of precision watches. Production of the Calibre 135 was discontinued in the 1960s, but its legacy lives on today. With this development, Zenith has managed to secure a firm place for itself in the world of haute horlogerie. Calibre 135 is still regarded as one of the best manual winding clockworks ever produced. Leather straps from protected species cannot be sent abroad. In these cases, the strap is removed before shipping. Vault watch, despite its age the watch is in excellent condition. From the collection of an important Cologne watch connoisseur. Box: yes. Papers: yes. Accessoires: no.