Patek Philippe Annual Calendar 5450

Patek Philippe's 2008 Annual Calendar Ref. 5450 was one of the first wristwatches with a full silicon escapement ever produced. It is the third member of their Advanced Research project.

Overview

In the 2000s, Patek Philippe set up an Advanced Research project to address the long-standing issues of isochronism and durability in watches. The main technology applied to this task was a proprietary alloy of silicon known as "Silinvar". The company proceeded steadily, producing first a Silinvar escape wheel, then a hairspring, an anchor, and a balance.

Ref. 5450 was the third Advanced Research watch, introduced in 2008. Cal. 324 S IRM QA LU included the Silinvar hairspring of its predecessor and added a Silinvar escapement. The company called this combination Pulsomax. This made it one of the first watches ever produced with a complete silicon escapement. The display caseback includes a large "cyclops" magnifier to allow the owner to inspect these high-technology components.

Although it used these high-tech components, Ref. 5350 was nevertheless a Patek Philippe. It included their revolutionary annual calendar mechanism with day and month subdials inset at 10:00 and 2:00, a date window below the moon phase indicator at 6:00, and a simple "+/-" power reserve indicator at 12:00. The salmon-colored dial features Arabic numerals at 3, 9, and 12, applied markers at all other hours but 6, and a "railroad" seconds track. The hour and minute hands are leaf shaped and feature lume. It has a traditional Patek Philippe platinum case, with long integrated lugs.

Reference: 5450 platinum, 300 produced Movement: Automatic manufacture movement: Caliber 324 S IRM QA LU, 28,800 A/h Annual calendar module Silinvar "Pulsomax" escapement with Silinvar Spiromax balance spring Geneva Seal Case: Platinum D 39 mm, H 11.7 mm Sapphire crystal caseback with magnifying bubble Dial: Salmon Functions: Hours, minutes, central seconds Annual calendar with day, date, month Moon phase indicator Limited edition: 300 pieces Successor: Patek Philippe Annual Calendar 5350 Successor: Patek Philippe Perpetual Calendar 5550