A moon you can rely on, even under cloudy skies: the perpetual calendar's high-precision moon phase display needs a one-day adjustment every 577.5 years. The moon phase display on the Portugieser Perpetual Calendar diverges by just 1 day in 577.5 years from the actual phase of the moon. The elegant timepiece leaves virtually no wish unfulfilled. It is equipped with features such as a perpetual calendar, a window showing the year in four digits and a 7-day automatic movement with Pellaton winding. The four subdials on the silver-plated dial display the phase of the moon, the date, month and day, the power reserve and the small seconds. This timepiece is powered by an IWC-manufactured movement from the 52000-calibre family, featuring a solid 5N gold rotor and blued screws. The 18-carat 5N gold watch has an arched-edge front glass and comes with a dark brown alligator leather strap.