Editorial
The Patrimony Perpetual Calendar Ultra-Thin is Vacheron's clearest argument that complications and restraint are not mutually exclusive. At 8.1mm total height with a perpetual calendar, retrograde date and day, and pointer-style month and year displays, it manages mechanical ambition with a silhouette that actually fits under a shirt cuff. Collectors who care about movement architecture will find the 1120 QP, derived from the JLC 920 family, one of the more intellectually satisfying calibers in this price tier.
The 43175 launched in 2014 as part of Vacheron's ongoing push to rationalize the Patrimony line around the ultra-thin aesthetic established decades earlier. The caliber 1120 QP is a perpetual calendar module built on the 1120 base, itself a Jaeger-LeCoultre 920-family movement that Vacheron, Audemars Piguet, and Patek each licensed and branded under their own references going back to the early 1970s. At 4.05mm, the movement is genuinely thin rather than marketing-thin, and the architectural choice to use retrograde indicators for date and day (avoiding the space-hungry conventional subdials) keeps the dial legible at 41mm.
The reference has been offered in rose gold and white gold with dial variations including cream, silver, and the more rarely seen slate grey. No major redesign has occurred since launch; Vacheron has treated it as a pillar reference rather than a platform for limited editions.
Verify that the perpetual calendar has been correctly set and not forced, particularly if the watch has sat unworn for any period, as advancing a perpetual calendar through prohibited hours can damage the mechanism. Inspect the case for wear at the lugs and bezel edge; rose gold at this gauge shows contact marks quickly, and light polishing is common on pre-owned examples that may have erased original finishing. Confirm all four perpetual calendar displays, date, day, month, and year, advance correctly at midnight on a full charge before accepting any private-sale piece.
The original bracelet or strap with correct buckle matters here because replacement Vacheron straps are expensive and period-correct alligator with the right clasp affects resale significantly. Service history documentation is worth requesting; the 1120 QP module requires a watchmaker comfortable with thin perpetual calendar work, and undocumented service is a yellow flag.