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Outbyte PC Repair FREERepair Windows errors before they cause bigger problemsFix Now →Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →Moritz Grossmann’s 2025 Perpetual Calendar is a hand-wound Glashütte high complication built around a distinctive peripheral date scale and a sum corrector designed to bring the calendar back in sync after the watch has stopped. It launched in two rose-gold versions and one platinum version, all powered by Calibre 101.13.
What is the Moritz Grossmann Perpetual Calendar?
A perpetual calendar, often abbreviated QP, is a mechanical complication that coordinates calendar indications across months of different lengths and leap years. Moritz Grossmann introduced this model as a 2025 novelty and a major complication marking the modern manufactory’s 17th anniversary. The manufacturer’s official product page presents the dial’s symmetry and date legibility as central design features.
How the calendar is displayed
The date scale, numbered 1 through 31, circles the dial’s perimeter. A cup-shaped framing indicator identifies the current date, keeping it visually distinct from the hour and minute hands. The weekday and month appear in subsidiary displays; leap-year and day/night indications sit within their centers. The moon phase is at 12 o’clock.
The effect is a calendar distributed around the dial rather than concentrated in a single date window. Its framing indicator makes the current date the focal point of the outer scale, while the smaller displays carry the other calendar information.
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How the sum corrector works
Recessed correctors in the case operate the calendar displays with a supplied special tool. The sum corrector is intended for a specific recovery situation: if the watch has stopped because it was not wound for a few days, it updates the date, and the weekday, month and moon phase follow automatically. This reduces the number of separate calendar indications that need to be reset after the lapse.
That feature does not mean the watch can never need adjustment. The maker describes a way to resynchronize displays after missed winding; it does not establish that every calendar indication will remain correct under all circumstances.
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- 1/20 Second Chronograph Measures up to 60 Minutes, Perpetual Calendar, 12/24 Hour Time, Power Reserve Indicator, Day/Date
- Silver-Tone Stainless Steel
- Anti-Reflective Sapphire Crystal
- 200 Meters water resistant and 5 year limited warranty
Three references: gold or platinum
The manufacturer’s 2025 English catalog identifies three official references. All have a three-part case and sapphire crystals; the documented case dimensions are 41 mm in diameter and 13.9 mm thick.
| Reference | Case | Dial | Hands |
|---|---|---|---|
| MG-003906 | Rose gold | Argenté | Hand-crafted, polished rose gold |
| MG-003907 | Rose gold | Charcoal | Hand-crafted, polished rose gold |
| MG-003904 | Platinum | Argenté/charcoal | Hand-crafted, blue-annealed steel |
The reference details are listed in the official 2025 English catalog. No water-resistance rating is stated in the launch coverage, so one should not be inferred from the case or sapphire crystals.
Rank #3
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Calibre 101.13: movement specifications
The hand-wound Calibre 101.13 is a manufacture movement regulated in five positions. Moritz Grossmann lists 401 components in total: 190 in the base movement and 211 in the calendar mechanism. It has 37 jewels, including four gold chatons, and a 42-hour power reserve.
| Specification | Calibre 101.13 |
|---|---|
| Winding | Manual |
| Regulation | Five positions |
| Components | 401 total: 190 base movement, 211 calendar mechanism |
| Jewels | 37, including four gold chatons |
| Power reserve | 42 hours |
| Frequency | 18,000 half-oscillations per hour |
| Balance diameter | 14.2 mm |
| Movement dimensions | 36.4 mm × 8.3 mm |
| Listed functions | Time, small seconds with stop-second, date, weekday, month and moon phase |
These are manufacturer specifications, not independent accuracy or wear-test results. The movement’s technical details are on the Calibre 101.13 page; the component split is also given in the manufacturer’s Perpetual Calendar press release.
Rank #4
- Timeless styling that effortlessly takes you from work to play.
- Analog Month/Day/Date, Moonphase Indicator
- Two-Tone Stainless Steel
- Spherical Mineral Crystal
- 100 Meters Water Resistant and 5 Year Limited Warranty
Price and availability
When accessed on 2026-10-08, the Grossmann Uhren GmbH boutique displayed a starting price of €98,800, including VAT and delivery/shipping. This is a dated page display, not a guaranteed future price; check the manufacturer-associated boutique product page for current price and availability. The manufacturer’s watch page also provides a retailer-finding route.
For context, Monochrome Watches reported launch-era prices on 2025-11-11 of €83,000 for rose gold and €91,800 for platinum. Those historical figures differ from the later boutique starting price and should not be treated as current pricing.
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1Repair Windows errors before they cause bigger problems2Fix the driver behind crashes, sound loss and screen glitches3Clear out junk files and repair common Windows errorsWhat the specifications establish—and what they do not
The documented proposition is a manually wound perpetual calendar with a 42-hour reserve, a date-forward dial layout and a mechanism for updating calendar displays after the watch has stopped. The published specifications establish the case dimensions, materials, references and movement figures, but they do not provide a water-resistance rating or independent performance findings. The available information supports describing the design and operation, not declaring it superior to other perpetual calendars.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
