Jaeger-LeCoultre Master Ultra Thin Moon: Rose Gold in a 36-millimeter case

Jaeger-LeCoultre is expanding the Master Ultra Thin Moon collection with a 36-millimeter rose gold model. The Q1242521 features a silver-colored dial with a moon phase display and a hand-operated date window at 6 o’clock. Inside, it is powered by the automatic Manufacture Caliber 925 with a 70-hour power reserve.

Smaller dimensions, familiar design

The case is made of 18-karat rose gold and measures 36 millimeters in diameter and 9.3 millimeters in height. Polished surfaces, a narrow bezel, and long, curved lugs define its silhouette. Its size echoes the proportions of classic round watches from the 1950s, clearly positioning this new model in the category of elegant dress watches.

On the silver-colored sunburst dial, the warm gold tone is echoed in the faceted hour markers and Dauphine hands. The hands feature alternating satin-finished and polished surfaces. The moon phase is set against a deep blue background studded with stars; the date is read on the scale surrounding it. The central seconds hand complements the hour and minute hands.

Caliber 925 with a 70-hour power reserve

The Master Ultra-Thin collection builds on Jaeger-LeCoultre’s expertise in flat movements, which dates back to the early 20th century. However, the slim profile is not an isolated feature: the calendar function, winding mechanism, and case proportions must all be harmoniously coordinated. In the new Moon, this task is handled by the Caliber 925, which is developed, manufactured, and assembled in Le Sentier.

The automatic movement has been one of the collection’s flagship calibers for many years and has undergone several technical upgrades. Its current version offers a 70-hour power reserve. This is equivalent to approximately three days and provides some leeway in everyday life when the watch is temporarily set aside.

The sapphire crystal case back reveals the decorated bridges, Geneva stripes, and blued screws. The openworked oscillating weight is crafted from 22-karat rose gold. It echoes the case’s material throughout the movement while also revealing parts of its architecture.

Black alligator leather and five bars

The watch is worn on a black alligator leather strap. An 18-karat rose gold pin buckle and the interchangeable strap system round out the features. It is water-resistant to five bar.