H. Moser & Cie. Endeavour Perpetual Calendar Concept Tantalum (Ref. 1800-2004): A Tantalum Case AND a Tantalum Dial on Moser's Signature Minimalist Perpetual, Limited to 50 Pieces

Description

Moser's Endeavour Perpetual Calendar has been, since its introduction in 2005, one of the purest expressions of minimalist haute horlogerie. Most perpetual calendars shout: four subdials, apertures, leap-year windows, moon phases. Moser's signature calendar does the opposite — a "concept" layout with no subdials, no leap-year indicator, and a tiny month-hand nested inside the hour pointer. You read all four calendar indications from the centre of the dial, with a clarity no other maker has achieved.

For Watches & Wonders 2026, the Endeavour Perpetual Calendar Concept arrives in tantalum — and not just on the case. For the first time in Moser's history, the dial is also crafted from tantalum. Limited to 50 pieces, it's a study in one of the rarest and hardest-to-machine metals in watchmaking, applied to a design that needs almost no visual noise to communicate its complexity.

Design

The case is 40mm across and 10.5mm thick, machined from tantalum — a dense, bluish-grey refractory metal that is roughly twice as heavy as stainless steel and almost impossible to scratch. Moser has polished the case for a cold, almost gunmetal sheen. The dial is a fumé-treated tantalum sheet, transitioning from a central bluish-grey to deeper charcoal edges — a departure from the enamel and lacquered dials Moser uses on its more traditional Endeavours.

Rhodium-plated leaf hands carry the hour, minute, and small seconds indications (the seconds register is subtly integrated into the lower half of the dial on many Concept pieces). The month is indicated by a short second hand layered over the hour hand — Moser's signature "flash calendar" architecture — and the date sits in a small window at 3 o'clock. The leap-year indicator is moved to the caseback, keeping the dial as clean as possible. A hand-stitched leather strap with a tantalum buckle completes the package.

Specifications

Reference: 1800-2004
Case size & material: 40mm × 10.5mm, tantalum, polished finish
Dial: Tantalum, fumé treatment
Crystal: Sapphire with anti-reflective coating, sapphire caseback
Hands: Rhodium-plated leaf
Water resistance: 30m
Strap: Hand-stitched leather with tantalum buckle
Movement: Calibre HMC 800 (in-house, manual-wind, Moser manufacture)
Complication: Perpetual calendar with instantaneous date change, Moser "flash calendar" architecture (month on short hour-hand pointer, day/date window at 3, leap-year indicator on caseback)
Frequency: 18,000 vph (2.5 Hz)
Power reserve: 7 days (168 hours) via twin barrels
Limited edition: 50 pieces
Price: USD 94,500

What's Exciting

Tantalum is a cruel metal to work with. It's so dense and resistant to wear that normal watchmaking tools struggle to finish it; most brands that use tantalum only use it on the case (Zenith's G.F.J. Tantalum from earlier in the show is a good comparison). Moser putting tantalum on the dial as well is a real technical flex — especially on a Concept dial that demands a flawless surface because there's almost nothing else to look at.

At USD 94,500 and only 50 pieces, it's priced firmly in the collector-grade perpetual calendar bracket (alongside pieces like JLC's Master Ultra Thin Perpetual Calendar in rose gold or the A. Lange & Söhne Langematik Perpetual). Moser's value proposition is the combination: a 7-day power reserve, the cleanest perpetual calendar dial in production, and a material that virtually no other brand is attempting at the dial level.

History

Moser first introduced the Endeavour Perpetual Calendar in 2005 — the watch that announced the revived brand's intent to play in serious haute horlogerie. It won the Grand Prix d'Horlogerie de Genève Men's Watch Prize in 2006. The "Concept" version, introduced in 2014, strips the dial back even further by removing the printed minute track, hour markers and moon phase, leaving only the fumé finish and a tiny leap-year window on the caseback.

Moser first released a tantalum Endeavour Perpetual Calendar in early 2023 (the Tantalum Blue Enamel edition with an enamel dial). The 2026 W&W release is the first time the brand has used tantalum for both case AND dial — a 21-year progression from the introduction of the HMC 800 calibre. The Tantalum Concept slots into Moser's ongoing material-experimentation series that has included damascus steel, globolite (cellulose-based) dials, and vanta-black ("Vantablack") dials.