Consider it a subtle but significant upgrade.
Jaeger-LeCoultre’s Master Ultra-Thin series is the definition of clean design. It’s a discreet dress watch that was built ultra-thin, not to break any world records, but to serve as a comfortable and elegant under-the-cuff classic watch. The Master Collection itself was introduced in 2008 to showcase Jaeger-LeCoultre’s considerable prowess in making classic complications—the company has more movements in its archives than any other brand. The Master Ultra-Thin moniker was attached to the model in 2012 to define the brand’s ability to create complications that are slim enough to qualify as elegant dress watches, and the Master Ultra-Thin Power Reserve complication came along in 2017, in both gold and steel models.
This year, it’s being refined slightly to have more power and a slightly updated dial. The movement, the automatic caliber 938, existed in the previous model, but it has been upgraded to increase the power reserve to 70 hours (from 43 hours). This significant gain was achieved without adding to the size of the movement, which remains 4.9 mm thick (the case measures a mere 39 mm wide x 8.95 mm thick). The mainspring barrel was redesigned, and Jaeger replaced some key components with silicon parts, which makes energy transmission smoother by reducing friction when the watch is running. The movement is an evolution of Jaeger-LeCoultre’s caliber 481, known as the Powermatic, from the 1940s, which was the world’s first self-winding timepiece with a power reserve gauge.
In addition to the power reserve indicator, the dial shows a date and a cross-hair small-seconds in subdials, in a slightly asymmetrical design, and it’s been given some updates. The subdials are slightly larger than the previous edition, for the sake of legibility, and the hour markers are elongated, which makes them look slimmer. Transferred gold dots mark the minutes. These gold markings and hands stand out against the brilliant midnight-blue sunray dial. It has a matching alligator strap. If you wind the watch manually, you can watch the power reserve indicator move—a fun pastime in boring meetings. The 18-karat rose gold case is inspired by the design of a case used on Jaeger-LeCoultre’s first ultra-thin pocket watch, designed in 1907. The new Master Ultra-Thin Power Reserve is priced at €19,800.
