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Jaeger-LeCoultre Master Control Geographic 40mm Stainless Steel
Ref. Q4128420
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Stepping up in Jaeger-LeCoultre's range
The Master Control Geographic carries JLC's GMT lineage forward on the Calibre 939AA, an in-house movement rebuilt around a silicon escapement and revised gear train to cut friction and extend the power reserve to 70 hours — a meaningful stretch over its predecessor, and enough to cover a long-haul weekend without winding. Every example is certified through JLC's 1,000-Hour Master Control programme, which tests the fully cased watch across six positions for timing accuracy, temperature response and power reserve efficiency. That is not a marketing claim mapped onto a movement test; it is a cased-watch test, which is a harder standard. At 11.0mm thick with a 47.5mm lug-to-lug span, it sits closer to a dress watch in the hand than most GMT pieces do, and on the wrist it tucks under a cuff without protest. The asymmetric dial layout — a deliberate echo of JLC's historic travel-time pieces — keeps the home-time subdial and power reserve indicator from feeling like additions, instead reading as part of a considered geometry. Heat-blued hands on the subdials sit against a sunray-brushed silver base, and the contrast holds in low light as well as it does in daylight. The Novonappa calf strap fits with quick-release spring bars, so changing it takes seconds rather than tools, and the double-folding deployant buckle allows fine adjustment on the wrist without having to remove the watch to do it.
- Reference
- Q4128420
- Brand
- Jaeger-LeCoultre
- Case size
- 40mm
- Case thickness
- 11mm
- Lug width
- 20mm
- Case material
- Stainless steel
- Case shape
- Round
- Dial
- Silver
- Crystal
- Sapphire
- Movement
- Automatic
- Calibre
- 939AA
- Functions
- GMT, Date, Power reserve indicator
- Water resistance
- 50m
- Bracelet / strap
- Leather strap
- Strap colour
- Brown
- Clasp
- Deployant clasp
- Lume
- Luminous
- Condition
- Pre-owned
- Retailer
- Mappin & Webb
Additional specifications
- Lug-to-lug
- 47.5mm
- Power reserve
- 70 hours
- Strap
- Interchangeable
Learn more about Jaeger-LeCoultre
Antoine LeCoultre opened a workshop in Le Sentier in 1833 and set about solving a problem nobody else had: precise measurement. His Millionomètre of 1844 was the first instrument capable of measuring to a micron, and it let the Vallée de Joux move from skilled approximation to genuine precision.
The house became the movement supplier to the industry. Patek Philippe, Vacheron Constantin, Cartier, and Audemars Piguet all built watches on LeCoultre ébauches, and the manufacture has produced well over a thousand distinct calibres — an output no other house approaches. The partnership with the Parisian retailer Edmond Jaeger, formalised in the company name in 1937, gave it the Jaeger-LeCoultre it still carries.
Two products define it in the public mind. The Reverso of 1931 was designed so British Army officers in India could flip the case and protect the crystal during polo; the reversible case became one of the few genuinely original watch designs of the century. The Atmos clock, developed from 1928, runs on atmospheric temperature variation and needs no winding at all.
The Duoplan and the calibre 101 — still the smallest mechanical movement in series production, introduced in 1929 — sit alongside the gyrotourbillons and minute repeaters that keep the manufacture at the technical front.
Richemont has owned the house since 2000.
- 1833
- Antoine LeCoultre founds his workshop in Le Sentier.
- 1844
- The Millionomètre measures to the micron for the first time.
- 1929
- Calibre 101, the smallest mechanical movement, is introduced.
- 1931
- The Reverso launches with its flip case.
- 1937
- The Jaeger-LeCoultre name is formalised.
Also in 6 collections
This watch appears in Stainless Steel Watches (2,797), Automatic Watches (1,432), Leather Strap Watches (918), Silver Dial Watches (628), Dress Watches (446) and Pre-Owned, Ex-Display & Vintage Watches (250).
What the specifications mean
A slim watch on leather, made for wearing with a shirt.
Strengths
- 40mm suits most wrists
- Sapphire crystal, which resists scratching
- 70-hour reserve survives a weekend off the wrist
- Luminous hands and markers for low light
- Second time zone for travelling
Worth knowing
- 50m suits rain and handwashing, not swimming
Compare alternatives
Watches from other brands at a similar price, style and size, so you can see what else your budget can buy.
| Specification | Q4128420 | 662.NX.1170.RX.1204 | O13125342055001 |
|---|---|---|---|
| Price | £11,350 | £12,000 | £14,500 |
| Case size | 40mm | 39mm | 41mm |
| Water resistance | 50m | 100m | 50m |
| Movement | Automatic | Automatic | Automatic |
| Strap | Leather strap | Rubber strap | Stainless steel bracelet |
| Power reserve | 70 hours | — | 55 hours |
| This watch |
|
|
Your new watch
Frequently asked questions, and things you should know about this watch
Can I swim with it?
Showering yes, swimming no. 50m covers splashes and brief immersion, but a swimming stroke generates well above the pressure that figure describes.
Will the glass scratch?
Unlikely. Sapphire is second only to diamond in hardness and shrugs off everyday marking.
Does it need a battery?
No. It is automatic — the motion of your wrist winds it, and there is no cell to replace.
How long does it run for when it's not worn?
About 70 hours fully wound — enough to sit off the wrist over a weekend and still be running.
What size strap does it take?
20mm. Any strap of that width will fit, and on most modern watches quick-release bars make the swap a two-minute job with no tools.
Will it fit my wrist?
Lug-to-lug is 47.5mm, which suits wrists from roughly 16.5cm (6½ inches) upward.
Lug-to-lug decides fit more than case diameter does.
Is it a men's or women's watch?
Listed as men's, though at 40mm it sits in the range that suits anyone.
Cheapest place to buy
Mappin & Webb at £11,350, pre-owned. No UK retailer we track lists this reference new.
Is this available new?
Not from the UK retailers we track. This reference is listed as pre-owned only, at £11,350 from Mappin & Webb. A pre-owned watch has been worn, and is normally sold under the retailer’s own warranty rather than the manufacturer’s.
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