79261

About the IWC 79261

Klaus's achievement was to make a perpetual calendar that needs no correctors. Every indication, the date, day, month, four-digit year and a moon phase accurate to one day in 122 years, advances together and is set forward from the crown alone, on a module of fewer than a hundred parts sitting on the 7750's chronograph. It made the perpetual calendar a watch IWC could build in series rather than to order, and the 7750 piece explains what the base gave it. The movement has 39 jewels, a 44-hour reserve and a 30 mm diameter; the 79261 is the later designation of the original 79061.

In the library it sits under 100 Da Vinci references, the ref 3750 and its successors in a 39 mm case, 24 GST Perpetual Calendars at 43 mm and 5 Pilot's Watches. The 39 mm case accounts for 91 references. 11 are limited editions.

The 79251 is the same movement with a split-seconds chronograph added, and the glossary defines the perpetual calendar it computes.