2022 Jaeger-LeCoultre Master Ultra Thin Box & Card

Jaeger-LeCoultre Master Ultra Thin Moon — Ref. Q1368430

IN PRODUCTION
There are thinner watches. There are watches with longer power reserves. There are watches with more complications. But there is almost nothing at any price that balances all of those things with the quiet confidence this reference carries. At 9.3mm thick and 39mm across, the Master Ultra Thin Moon occupies the exact dimensional sweet spot where a watch disappears under a shirt cuff and then stops a conversation when it comes out — and the moon phase at 6 o'clock is the reason it stops conversations. The blue-background display with its silver moon and stars sits inside a date pointer that tracks the perimeter of the subdial, combining two complications into a single visual element that reads as pure decoration until someone asks what the hand is doing, and then it becomes the most elegant date display in watchmaking. The sunray-brushed silvered dial, polished dauphine hands, and rhodium-plated facetted indexes are deliberately restrained — every design choice on this dial exists to keep your eye moving toward that moon phase, and nothing competes with it.
The Cal. 925AA is an entirely in-house manufacture movement, designed, built, and assembled under one roof in the Vallée de Joux — and JLC doesn't certify it through COSC because they consider their own 1000 Hours Control to be more rigorous. That's a six-week testing protocol that evaluates accuracy, water resistance, power reserve, and shock resistance in the fully cased watch, not just the naked movement, and it's been the standard for every Master collection piece since 1992. The 70-hour power reserve means a full weekend off the wrist with time to spare, the exhibition caseback puts the finished movement on display through sapphire, and the alligator strap features JLC's quick-release spring bar system for tool-less swaps — a detail that turns a single-strap dress watch into a rotation piece that takes thirty seconds to restyle. Everything about this reference says that the people who built it understand the difference between a watch that's impressive and a watch that's beautiful, and chose beautiful every time.
Key Details

• Case diameter: 39 mm
• Case thickness: 9.3 mm
• Lug-to-lug: ~46 mm (not officially published; collector-measured)
• Lug width: 21 mm
• Buckle width: 18 mm
• Weight: not officially listed
• Case material: stainless steel, fully polished
• Case design: slim bevelled lugs, slim bezel, large dial opening
• Crystal: sapphire, scratch-resistant
• Water resistance: 50 m / 5 bar
• Caseback: transparent/exhibition (sapphire)
• Bezel: fixed, polished stainless steel
• Dial: silvered grey, sunray-brushed, slightly domed
• Hands: polished dauphine ("Recto" hands)
• Hour markers: rhodium-plated, applied, facetted
• Moon phase: subdial at 6 o'clock, blue background with silver moon and stars
• Date: pointer hand encircling moon phase subdial
• Caliber: Jaeger-LeCoultre 925AA (manufacture, in-house)
• Movement type: self-winding automatic
• Frequency: 28,800 vph / 4 Hz
• Jewels: 30
• Components: 245
• Power reserve: 70 hours
• Testing: JLC 1000 Hours Control (proprietary 6-week protocol; accuracy, water resistance, power reserve, and shock resistance tested in fully cased condition)
• Strap: black alligator leather, large scales, quick-release spring bars for tool-less interchangeability
• Clasp: double folding buckle, stainless steel