IWC SCHAFFHAUSEN Portugieser Eternal Calendar presented at Watches and Wonders 2024.

IWC SCHAFFHAUSEN Portugieser Eternal Calendar with Moon Phase accuracy of 45 Million Years. The watch is based on the same design as the existing perpetual calendar. All its displays can be advanced using the crown. However, while the perpetual calendar is programmed for a four-year cycle, the Portugieser Eternal Calendar features an additional mechanism. Every four years at the end of February, a new module informs the calendar about whether the leap year takes place or not. This so-called 400-years gear completes only one revolution every four centuries. It contains three indentations, which cause the calendar to skip three leap years over that period.