Longines Ultra-Chron Classic automatic silver dial leather strap 37 mm

Ultra-Chron: A Legacy of Precision

The history of Longines is closely linked to the pursuit of precision, a value that has shaped its reputation since the early 20th century. In 1910, the winged hourglass brand filed a patent for a pocket chronograph capable of measuring 1/10th of a second — an extraordinary achievement for the time, made possible by a movement beating at 5 Hz (10 vibrations per second). This innovation marked the beginning of a long tradition in the field of high-frequency watchmaking.

In 1959, Longines took a decisive step forward by developing the Calibre 360, the first 5 Hz wristwatch movement, specifically designed for observatory competitions. This rectangular calibre achieved exceptional performance: during chronometry contests at the Neuchâtel Observatory, it recorded a daily deviation of less than 1/10th of a second, taking first and second place in 1961, and once again dominating in 1962. This mastery proved that high frequency was not just a technical feat, but a practical way to improve stability and rate regularity, particularly against shocks, changes in position, or temperature variations.

Building on this success, Longines decided to adapt this advanced technology for large-scale production. In 1967, the brand unveiled the Ultra-Chron, the first mass-produced high-frequency automatic wristwatch, equipped with the Calibre 431 featuring patented dry lubrication and an instantaneous jumping date. The performance was such that the brand guaranteed an accuracy of ±2 seconds per day, or one minute per month, far surpassing the standards required by conventional chronometer certifications. The following year, the Ultra-Chron Diver became one of the first high-frequency dive watches, proving that precision could also go hand in hand with robustness.

This pursuit of chronometry helped establish Longines as one of the leading names in sports timekeeping, whether in alpine skiing, equestrian competitions, or other disciplines where fractions of a second are decisive.

Nearly six decades later, Longines reaffirms this legacy. Following the acclaimed return of the Ultra-Chron Diver in 2022, the brand unveiled in 2025 the Ultra-Chron Classic, a faithful re-edition of the 1967 reference 7827. This revival does more than resurrect a heritage design: it is powered by the exclusive Calibre L836.6, introduced in 2022, featuring a silicon balance spring, enhanced magnetic resistance, and full-watch chronometer certification by TIMELAB in accordance with the ISO 3159 standard.

The Ultra-Chron Classic thus embodies the philosophy of Longines: honoring the past without abandoning contemporary advancements. It demonstrates that a design born in the 1960s, when combined with today’s technical standards, can offer collectors and enthusiasts an authentic watchmaking experience with exemplary precision.

Revisited Vintage Design

The Ultra-Chron Classic 37 mm is a direct tribute to the elegance and refinement of the original 1967 model. Longines sought to recapture the spirit of the watch that epitomized horological modernity of its time, while subtly adapting it to meet the expectations of today’s collectors.

At first glance, the 37 mm stainless-steel case, with its slender 10.95 mm profile, impresses with its balanced proportions, very close to the historical 35 mm. This deliberate choice reflects the brand’s commitment to preserving the compact, refined look of the original piece, ideal for wrists seeking comfort and understated sophistication.

The charm is also evident in the domed, sunray-brushed silver dial, a true signature of the Ultra-Chron. Its soft reflections capture the light with the same delicacy as the 1967 model and highlight the central crosshair, another emblematic graphic element of the era.

At 6 o’clock sits the historic applied Ultra-Chron logo, finely polished and slightly raised, complemented at 12 o’clock by the iconic Longines winged hourglass emblem. This distinctive detail, faithfully reproduced from the original model, underscores the heritage character of the watch and reinforces its authenticity.

The faceted applied rhodium-polished hour markers and baton hands are filled with black lacquer — a deliberate choice that faithfully reflects the vintage aesthetic, though it does not include luminescence.

The trapezoidal date window at 3 o’clock, featuring the same typography as the historic Calibre 431, pays homage to the past and contributes to the visual harmony of the dial. The whole is protected by a box-shaped sapphire crystal, domed like the acrylic crystals of the period but treated with a multi-layer anti-reflective coating on both sides, ensuring excellent legibility and durability.

On the reverse side, the solid screw-down caseback displays the historic Ultra-Chron logo and the engraving “Chronometer officially certified,” a symbol of the chronometric excellence that has defined this model since its origins.

Water-resistant to 5 bar (50 m), the Ultra-Chron Classic 37 mm is not intended as a professional diver’s watch but offers sufficient protection for daily wear.

The black alligator leather strap gives the Ultra-Chron Classic 37 mm a distinctly dressy character, perfectly in tune with the model’s heritage spirit.
Its pronounced natural grain and deep hue highlight the elegance of the silver dial while adding a timelessly classic touch. The polished heritage-style steel pin buckle, inspired by the clasps of 1960s watches, completes the vintage look and ensures a secure and comfortable fit on the wrist.
Supple and pleasant to wear, this leather strap offers a more refined and formal alternative to the steel bracelet, while staying true to the historical essence of the collection.

Every design detail has been carefully considered to revive the spirit of the 1960s while ensuring the comfort and reliability of a modern timepiece. The Ultra-Chron Classic 37 mm is thus a faithful, elegant, and understated re-interpretation of a milestone in Longines’ watchmaking history.

High-Frequency Calibre L836.6

The heart of the Ultra-Chron Classic 37 mm beats with the exclusive Longines automatic Calibre L836.6, a direct heir to the brand’s century-long expertise in high-frequency watchmaking.

Introduced in 2022 for the re-edition of the Ultra-Chron Diver, the Calibre L836.6 continues the spirit of the legendary 1967 Calibre 431 while incorporating cutting-edge innovations.
Beating at a fast rate of 5 Hz (36,000 vibrations per hour) — equivalent to ten oscillations of the balance wheel per second — it ensures superior rate stability, as deviations caused by shocks, positional changes, or accelerations are corrected more rapidly than with traditional 3 Hz or 4 Hz movements.

At the core of this movement, the silicon balance spring is one of its most important assets. Lighter and unaffected by temperature variations or magnetic fields, it provides the calibre with magnetic resistance ten times higher than the ISO 764 standard. This ensures not only long-term precision but also reliable performance in the face of modern-day environmental challenges.

The Calibre L836.6 also delivers a comfortable 52-hour power reserve, more than sufficient for alternating between watches without the need for frequent winding.

Another significant distinction: unlike conventional certifications that apply only to the movement, the Ultra-Chron Classic is certified as a chronometer by TIMELAB under the ISO 3159 standard after tests conducted on the fully assembled watch.
For 15 days, the watch undergoes rigorous trials: positioned in various orientations and exposed to three different temperatures (8 °C, 23 °C, and 38 °C), it must maintain exemplary precision.
This approach guarantees that chronometric excellence is ensured not only in the laboratory but also in real-world conditions.

With this movement, the Ultra-Chron Classic 37 mm does more than honor the past: it revives the promise that made the original collection successful — certified, enduring precision worthy of a true “Ultra-Chronometer.”