Jaeger-LeCoultre Master Ultra Thin Moon automatic silver dial black leather strap 36 mm

Master Ultra Thin: Poetry and Watchmaking Tradition

For more than 190 years, Jaeger-LeCoultre has mastered the art of combining technical expertise with refinement. Launched in the 1990s, the Master Ultra Thin collection embodies this pursuit of balance between understated elegance and mechanical excellence. Among its most emblematic creations, the Master Ultra Thin Moon stands out with the integration of a complication that is both useful and poetic: the moon phase indication.
Reference Q1248421 carries on this legacy in a contemporary interpretation: an ultra-thin steel timepiece with a timeless design and a celestial complication beautifully displayed at 6 o’clock.

A Refined Design with Celestial Accents

With its 36 mm stainless steel case and a thickness of just 9.3 mm, the Master Ultra Thin Moon charms with its balance and discretion. Its ideal proportions make it the perfect dress watch, easy to wear on a daily basis as well as for formal occasions.

The silvered sunray dial subtly captures the light, highlighting the polished and satin-finished Dauphine hands, along with the applied baton indexes. Yet it is at 6 o’clock that the poetry of this model reveals itself: a deep-blue moon phase adorned with stars and a silver moon captivates the eye, evoking the intimate link between watchmaking and celestial cycles. Surrounding this display, a date indicated by a central hand harmoniously completes the composition.

The Jaeger-LeCoultre Calibre 925: Fineness and Performance

The Master Ultra Thin Moon Q1248421 is powered by the automatic Calibre 925/1, a manufacture movement entirely developed and assembled in the Vallée de Joux.

• Movement thickness: 4.9 mm, a feat of miniaturization.
• Power reserve: 70 hours, enough to set the watch aside over a weekend without needing to reset it.
• Frequency: 28,800 vibrations per hour (4 Hz).
• Components: 245 finely decorated parts, visible through the transparent sapphire caseback.

Each movement undergoes the exclusive “1,000 Hours Control” protocol, a rigorous in-house testing procedure that guarantees reliability and precision in all conditions of use.

An Elegant Timepiece for Everyday Wear

Lightweight, comfortable, and fitted with a hand-stitched black alligator strap, the Master Ultra Thin Moon combines refinement with practicality. Its water resistance of 5 bar (50 meters) ensures sufficient protection for urban life, while its slender profile makes it the perfect companion for formal attire. The stainless steel folding clasp enhances comfort and security on the wrist, while adding an extra touch of elegance.