Patek Philippe Annual Calendar Moonphase Factory Certified Pre-Owned Reference 581

Reference 581

While the Seamaster collection of waterproof watches had been in production since the 1940s

From the dawn of the 20th century onward

Chief among these innovations was an increased depth rating (300m

Patek Philippe Annual Calendar Moonphase Factory Certified Pre-Owned Reference 581The annual calendar is a complication invented by Patek Philippe. While it plays second string to the perpetual calendar in the minds of most collectors, the reality is that the construction of the calendar mechanism is equally challenging and, in some cases, requires even more components. 1996's Ref. 5035 was Patek's first annual calendar model and set the bar for all that followed including those from competitors. This particular annual calendar, a