Movement record · Switzerland
Jaeger-LeCoultre Calibre 920
Partially verifiedAn extremely thin automatic movement using a 22-carat gold peripheral micro-rotor rather than a full rotor, allowing exceptional slimness; supplied by Jaeger-LeCoultre to several prestige houses and adapted as the basis for celebrated in-house calibres elsewhere.
Technical specifications
- Diameter
- Approx. 28 mm
- Height
- Approx. 2.45 mm
- Jewels
- Approx. 28
- Frequency
- 19,800 vph
- Power reserve
- Approx. 40 hours
- Winding
- Self-winding with a peripheral micro-rotor
- Setting
- Pull-out crown
- Escapement
- Swiss lever
- Balance
- Conventional balance with flat hairspring
- Complications
- Date on some applications
Identification features
- Micro-rotor construction visible from the case-back
- Exceptional thinness for an automatic movement of its date
Known variants
- Manufacturer-specific finishing and branding of the shared base architecture
Servicing notes
Specialist high-end servicing recommended given the movement's thinness and the finishing standards expected of its applications.
General guidance only. Antique movements should be serviced by a qualified watchmaker.
Historical significance
A landmark in ultra-thin automatic construction and an unusually clear example of one ébauche underlying several 'in-house' prestige calibres.
Related photographs
No confidently matched photograph of this subject has been found yet. These photographs show a closely related record, and are not examples of the type described on this page.
Sources & references
- Jaeger-LeCoultre and licensee historical literature
- Independent watch-industry technical histories
Where sources disagree, the disagreement is stated rather than resolved silently.