Patek Philippe Annual calendar in 18 k rose gold ref 5396RThe Patek Philippe Reference 5396 Annual Calendar, introduced in 2006, marked a significant evolution of the brands annual calendar complication. It combines a classic Calatrava style case with a pioneering twin in line display for the day and month. This design, which pays homage to the aesthetic of Pateks early perpetual calendars, was launched to commemorate the 20th anniversary of the brands original annual calendar patent. A key innovation lies