Jaeger-LeCoultre Master Ultra Thin Master Ultra Thin Réserve de Marche Stainless Steel / Silver / Alligator
Reference Q1378421
About this watch
The Jaeger-LeCoultre Master Ultra Thin Power Reserve Q1378421 debuted in .
This elegant stainless steel dress watch features a 39 mm case with polished and satin-finished surfaces, framing a silvered sunray dial. Refined elements include elongated hour markers, dauphine hands, and three recessed opaline subdials for the power reserve, date, and small seconds functions—each laid out in a symmetrical and harmonious arrangement.
Inside ticks the automatic caliber 938, developed and manufactured in-house by Jaeger-LeCoultre. With a silicon escapement and a single barrel, it delivers a 70-hour power reserve. The Q1378421 is paired with a light brown leather strap fitted with a stainless steel double folding clasp.
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Specifications
- Brand
- Jaeger-LeCoultre
- Family
- Master Ultra Thin
- Model
- Master Ultra Thin Réserve de Marche Stainless Steel / Silver / Alligator
- Reference
- Q1378421
- Movement
- 938
- Movement Features
-
- Hours, Minutes, Small Seconds
- Date
- Power Reserve Indicator
- Case
- Stainless Steel 39mm
- Dial Color
- Silver
- Crystal
- Sapphire
- Water Resistance
- 50
Current Listings
![[WTS] 12 Days of Christmas 🎄 | Day 6/12 | Jaeger-LeCoultre Master Ultra Thin Tourbillon 40mm ✨](https://external-preview.redd.it/NjYxdHN5ZWZlZWFnMc759IRhaq6cjVz_tatgefDVzRQHQytIWNBthhQ3SJit.png?format=pjpg&auto=webp&s=6bfc38444dd615a5f6b09c90897216d7c6fcbf3a)
12 Days of Christmas 🎄 | Day 6/12 | Jaeger-LeCoultre Master Ultra Thin Tourbillon 40mm ✨
A Jaeger-LeCoultre Master Ultra Thin Tourbillon watch that showcases a tourbillon movement in an ultra-thin case, balancing form and function. This watch rewards curiosity and inspires wonder.
- Movement: in-house JLC tourbillon movement
- Case construction: ultra-thin
- Dial style: balanced, uncluttered dial with traditional finishing and proportions
![[WTS] Jaeger-LeCoultre Master Ultra Thin Moon 39mm Q1368470 $5,850](https://preview.redd.it/nzl80wv0cu9g1.jpg?width=640&crop=smart&auto=webp&s=4f9d8d34f90a016d6441a32beafe3f85cccbd660)
Jaeger-LeCoultre Master Ultra Thin Moon 39mm Q1368470 $5,850
A Jaeger-LeCoultre Master Ultra Thin Moon in Black with a deep black sunburst dial and extremely thin profile, making it a classy and elegant dress watch.
- Condition: Very Good
- Box Papers: Yes (dated April 2019)
- Warranty Years Left: 8
![[WTS] 12 Days of Christmas 🎄 | Day 3/12 | Jaeger-LeCoultre Master Ultra Thin Date ✨](https://preview.redd.it/flwkjiupns9g1.jpeg?auto=webp&s=15d1c603309630076d2dcf0bb0adc99bb1ab2c31)
12 Days of Christmas 🎄 | Day 3/12 | Jaeger-LeCoultre Master Ultra Thin Date ✨
The Jaeger-LeCoultre Master Ultra Thin Date is a 39mm stainless steel watch with a silvered sunray-brushed dial and black leather strap, featuring an automatic movement.
- Case size: 39mm
- Material: stainless steel
- Dial finish: silvered sunray-brushed
![[WTS] Jaeger-LeCoultre Master Ultra Thin Small Seconds 39mm Pink Gold Q1212510](https://preview.redd.it/i4zcktiat68g1.jpg?width=640&crop=smart&auto=webp&s=480dc3c930c953993d892ac1b8eae3020f62a9b3)
Jaeger-LeCoultre Master Ultra Thin Small Seconds 39mm Pink Gold Q1212510
A Jaeger-LeCoultre Master Ultra Thin Small Seconds in pink gold with a 39mm case size.
- Condition: Very good, rated at 9.7/10
- Case Size: 39mm
![[WTS] Jaeger-LeCoultre Master Ultra Thin Moon Rose Gold Box and Papers Q1362510](https://preview.redd.it/jyo1ltz6o28g1.jpg?width=640&crop=smart&auto=webp&s=572516763603d4e3c7db363933c38baa1fef4ca1)
Jaeger-LeCoultre Master Ultra Thin Moon Rose Gold Box and Papers Q1362510
- Case material: rose gold
- Box and papers: yes
![[WTS] Jaeger-LeCoultre Master Ultra Thin Moon – 39mm – Warranty to 2031](https://preview.redd.it/p54i82z6qt7g1.jpeg?auto=webp&s=6eb0a4d1cdae42352607751a7a64186cd2863aaf)
Jaeger-LeCoultre Master Ultra Thin Moon – 39mm – Warranty to 2031
The Jaeger-LeCoultre Master Ultra Thin Moon is an elegant and striking watch featuring a reworked 39mm case, updated moonphase disc, and new-generation Caliber 925 movement with 70-hour power reserve.
- Case size: 39mm
- Movement: Caliber 925 with 70-hour power reserve
BNIB Jaeger-LeCoultre MASTER ULTRA THIN MOON STAINLESS STEEL 2025 FULL SET
A Jaeger-LeCoultre Master Ultra Thin Moonphase watch in stainless steel with a silver dial, featuring a 39mm case and a black alligator leather strap. The watch is complete with its original packaging and comes under an 8-year factory warranty.
- Condition: Brand New In Box (BNIB)
- Case size: 39mm
- Material: stainless steel
- Strap material: black alligator leather
BNIB Jaeger-LeCoultre MASTER ULTRA THIN DATE BLUE DIAL Q1238480 2025 FULL SET
This is a brand new Jaeger-LeCoultre Master Ultra Thin Date with a blue dial and 39mm stainless steel case, on a black alligator leather strap.
- Condition: Brand new in box (BNIB)
- Case size: 39mm
- Material: stainless steel
2023 JLC Moonphase Master Ultra Thin
The Jaeger-LeCoultre Master Ultra Thin Moon combines a refined, minimalist design with the sophisticated complication of a moon phase indicator in a sleek, ultra-thin case that measures just 9.3mm thin.
- Condition: Excellent Unworn Condition
- Case Material: Stainless steel
- Dial Color: Silver-Grey
- Movement Type: Automatic