Editorial
The 5650G is a single-year Advanced Research edition that wrapped Patek's travel time complication in a 40.8mm white gold Aquanaut case and debuted two proprietary technologies: the Spiromax silicon balance spring and the Pulsomax silicon escapement, plus a flexible composite strap hinge called Caoutchouc. Produced only in 2017, it sits in the Advanced Research line that Patek uses to field-test materials and mechanisms before mainline production. Collector demand is real and consistent because the 5650G is both a working travel time watch and a documented technology milestone.
The Advanced Research series launched in 2005 as a platform for testing silicon-based movement components, and the 5650G is the fifth reference in the program. It uses caliber 324 S C FUS, a self-winding movement with an instantaneous-jumping local time display and a patented flexible strap attachment that eliminates the rigid lug-to-case junction found on standard Aquanaut references. Patek produced the 5650G in 2017 only, with official allocation through boutiques and select authorized dealers.
No subsequent production runs were announced, and no dial variants exist. The "FUS" suffix on the caliber designates the Spiromax/Pulsomax silicon component package.
Confirm the flexible strap hinge is intact and operates smoothly before purchase. The composite hinge mechanism is unique to this reference and cannot be sourced from a standard Aquanaut parts supply. Ask for the original Patek box, papers, and any Advanced Research documentation; the 5650G was delivered with reference materials explaining the technology, and a set without these raises authenticity questions.
The white gold case should show typical light surface wear only. Any polishing history significantly reduces collector value on a watch produced in this volume. Verify the silicon escapement has not been replaced with a conventional lever-and-balance assembly during a prior service, which would defeat the technical purpose of owning an Advanced Research piece.
