Longines Caliber L836.6

The Longines caliber L836.6 is a high-beat 3-hander automatic watch movement found in the modern Ultra-Chron reissue. The L836.6 is a true no-date movement and powers the Ultra-Chron diver, which Longines refers to as “The Ultra Most Accurate Watch”.

Despite this movement being ultra marketed by Longines, the models powered by the L836.6 have solid casebacks.

Not only do the watches themselves offer no view into the movement, but Longines appears to only provide one low resolution image on their site, and a quick glimpse in a video…

High-Beat:

The L836.6 is a high-beat movement with a rate of 36,000 beats or vibrations per hour. That translates to a frequency of 5 Hz or 10 “ticks” per second.

Int he brand’s own words:

“The new high-frequency movement guarantees higher precision and profits from Longines’ rich heritage of producing high-beat movements for over 100 years. Inspired by the original Longines Ultra-Chron Diver of 1968, the new model reflects the iconic design codes of its ancestor.” –Source

Audio: Listen to the L836.6 hi-beat movement

Ultra Chronometer:

The L836.6 is supposed to perform better than a standard chronometer rated or COSC certified automatic watch movement.

“The accuracy of the Longines Ultra-Chron is confirmed by its certification as an “ultra chronometer” by TIMELAB, an independent testing laboratory in Geneva. This designation goes beyond the usual “chronometer” certification.” – Source

Is the L836 an In-House Movement?

Although some Longines marketing material has called this calibre “in-house” (specifically presented as such in the video below), it is more accurate to call it a manufacture or exclusive caliber since it is in fact produced by ETA and you can see the ETA shield logo near the balance wheel in the stock photo. While Longines and ETA are both members of the Swatch Group conglomerate of watch companies, the movement was not produced by Longines independently, therefore it is technically an ETA movement produced for Longines.

Video – Longines Ultra-Chron – Key Features:

Additional Resources:

• Official instructions manual (pdf)