====== Patek Philippe Annual Calendar 5450 ======

{{wst>image_cr|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 [[Patek Philippe Advanced Research|Advanced Research]] project.

===== Overview =====
In the 2000s, Patek Philippe set up an [[Patek Philippe Advanced Research|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]]. [[PP 324|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. 5450 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.

<WRAP ud ud_mod>
**Reference:**
  * 5450 platinum, 300 produced

**Movement:**
  * [[Automatic]] [[manufacture]] movement [[PP 324|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]]
</WRAP>

{{tag>Watch_models Watches_with_annual_calendar Patek_Philippe_models Patek_Philippe_references Patek_Philippe_Advanced_Research_models}}