Our remarks

PATEK PHILIPPE Advanced Research Perpetual Calendar Moon Phase Ref. 5550P-001 950 Platinum Folding Clasp Box Papers Bj-2012 WEMPE Very Rare Limited 300 Pieces Full Set

We are honoured to present a true landmark of modern Patek Philippe engineering: the Advanced Research Perpetual Calendar, Ref. 5550P-001, limited to just 300 examples worldwide. Unveiled as the fourth and final chapter of Patek Philippe's Advanced Research programme, this reference holds a special place in the manufacture's history as the first Patek Philippe watch ever equipped with a complete silicon escapement, uniting the escape wheel, pallet fork, balance wheel, and hairspring all in Silinvar.

Housed in a beautifully proportioned 37mm platinum case, complete with the brand's traditional diamond set between the upper lugs to signify the precious metal, the 5550P presents a striking silvered dial with fine vertical brushing that shifts character with the light. Rose gold hour markers and feuille hands, generously filled with luminous material, sit alongside the moon phase and full perpetual calendar display, combining Patek Philippe's most traditional complication with a genuinely modern, technical dial architecture.

At the heart of the watch beats the automatic Caliber 240 Q Si, built around the legendary micro rotor Caliber 240 and enhanced by Patek Philippe's Oscillomax assembly, comprising the GyromaxSi balance wheel with adjustable gold weights, the Pulsomax escape wheel and lever, and the Spiromax hairspring, together the subject of seventeen patents. 

The result is a power reserve increased by roughly 50 percent over the standard Caliber 240, from 48 hours to approximately 70 hours, along with markedly improved resistance to temperature variation, magnetism, and shock, all without the need for lubrication of these critical components. A sapphire display back, fitted with a discreet magnifying lens, allows collectors to study the Oscillomax system directly, a rare invitation from Patek Philippe into its own research and development.

Completing the watch is its platinum folding clasp, offering secure comfort in keeping with the understated elegance of the case.

This Patek Philippe Advanced Research Perpetual Calendar Ref. 5550P-001 is offered as a set consisting of:

- Patek Philippe outer box and special presentation box with watch winder

- Warranty Certificate, 2012

- Leather card holder

- 2nd platinm back

- Setting pin 

- Hang Tag

- Limited edition of 300 pieces

- High-End collectors piece

- WEMPE 

"The Ref. 5550P is the watch where Patek Philippe quietly proved that its most traditional complication and its most forward looking research could share the same platinum case. A true collector's grail from the Advanced Research series.“