Q1378421
- Model
- Master Ultra Thin Power Reserve
- Case material
- Stainless Steel
- Case size
- 39mm
- Movement
- Automatic
- Calibre
- 938
- Dial colours
- Silver / White
- Market value band
- $6k – $45k
Q1378421 is a Jaeger-LeCoultre Master Ultra Thin Power Reserve reference.
The case is 39mm stainless steel.
It runs the 938, an automatic movement.
Catalogued dial colour: silver / white.
Re-verified 2026-08-24. Header spec line: '39 mm Automatic Steel Power Reserve Ultra Thin Watch'. Body copy: silver sunrayed dial; in-house Calibre 938, silicon escapement, 70h power reserve (not exposed at the time of the prior pass).
Before you ask.
What movement does the Jaeger-LeCoultre Q1378421 use?
The Jaeger-LeCoultre Q1378421 runs the 938, an automatic movement.
How do I check a Jaeger-LeCoultre Q1378421 with Watch Safe?
Look up the watch's serial number in the Watch Safe registry to see whether a record exists or a theft flag is attached. A registry search identifies records for a specific serial; it does not authenticate the watch. Authentication is performed in person by an independent expert authenticator, and Watch Safe records and publishes the result.
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