The open-worked form and trippy, celestial dial of H. Moser‘s Endeavour Minute Repeater Cylindrical Tourbillon Skeleton Cosmic Rain are definitely eye-catching, but watch fans know from the name alone that this is a mechanical marvel. The convergence of two elements in particular—a minute repeater displayed on the dial side and a flying tourbillon fitted with a cylindrical hairspring—is a particularly mind-blowing feat that few other watchmakers have attempted.
The minute repeater on its own is already one of the most intricate complications, with a mechanism that chimes the time acoustically at the press of a button, triggering tiny gong strikes inside the case—a low-pitched chime for each hour, a two-tone chime for each quarter-hour, and a high-pitched chime for every minute past the last quarter.
Instead of typical positioning hidden away behind the movement, H. Moser redesigned the architecture to ensure the tiny hammers and gongs are entirely visible on the dial side. The one-minute flying tourbillon—another prestige complication that counteracts the effects of gravity on a watch’s accuracy—is fitted with a cylindrical hairspring. Inherited from 18th-century marine chronometers, this hairspring rises perpendicularly around the upper stem of the balance staff. Its conical shape improves accuracy but required production from Precision Engineering AG, a sister company of H. Moser & Cie., as each hairspring is hand-shaped.
At the 2 o’clock position, the transparency of the skeletonized movement gives way to a small cosmic dial made of aventurine—a glass first made in the 18th century that shimmers with an infusion of tiny copper crystals. For this piece, aventurine fragments in two colors were hand-applied to a domed base to create H. Moser’s signature smoky look. Then, thin strips of mother-of-pearl were cut, curved, and set into the engraved surface, following the dial’s contours, to create a visual effect that’s meant to resemble a shower of stars across the night sky. All of this is housed in a 40-mm titanium case and secured to a gray nubuck alligator leather strap.
Reportedly priced at an astronomical $440,000, the H. Moser Endeavour Minute Repeater Cylindrical Tourbillon Skeleton Cosmic Rain is limited to 20 examples that are available to reserve now.