IWC Portugieser Perpetual Calendar

The Portugieser Perpetual Calendar is IWC's masterpiece. Kurt Klaus conceived the calendar module in the 1980s with an elegance that still astonishes: date, day, month, four-digit year and moon all advance from a single mechanical programme requiring no correction until 2100, and the entire calendar is set through the crown alone. The double moonphase deviates by one day in 577.5 years.

Reference: IW344203
Movement: Automatic, in-house calibre 82650 with Pellaton winding
Power reserve: approx. 60 hours
Case: Stainless steel, 42.4 mm
Complications: Perpetual calendar, four-digit year, moon phase
Water resistance: 30 m
Year: 2026 — Full set