Few complications command the reverence of a Patek Philippe perpetual calendar, engineered to track the date correctly until the year 2100. It is the kind of watch a family hands down rather than trades away. For the collector who already owns the icons, this is the quiet piece that outclasses them all.

Presents itself in mint condition with little to no signs of wear. Set against a sunburst blue dial, applied white gold Breguet numerals frame the day, date, month, and moon phase. Carved from 18K white gold, the Calatrava style case shows mirror polished flanks and softly curved lugs. Viewed through the sapphire caseback, the ultra thin caliber 240 Q reveals Geneva striping and a 22K gold micro rotor. Wrapped in navy alligator and closed by a signed white gold clasp, it finishes as beautifully as it begins.

Functions include hours, minutes, day, date, month, leap year, 24 hour indication, and moon phase. Set at 3 o’clock, the crown winds the movement when pushed in and sets the time when pulled out. Recessed correctors on the case flanks, used with the supplied stylus, adjust the day, date, month with its leap year cycle, and moon phase. After the watch has rested, wind about thirty turns, set the calendar to the day before today, then carry the hour hand forward through midnight to the correct time, never turning the hands backward and never using the correctors between 8:00 PM and 3:00 AM. Fully wound, the self winding caliber 240 Q holds 38 to 48 hours of power reserve and is water resistant to 30 meters.

Comes as a full set, double-boxed with Certificate of Origin, leather document folio, correction stylus, solid 18K white gold caseback, Genève hang tag, leather travel case, and protective cloth.

Own the perpetual calendar and you own watchmaking’s final word, built to outlast both trends and its owner. Understated enough to wear every day, serious enough to anchor a collection. Some watches are simply bought, but this is the kind one keeps.