Jaeger-LeCoultre: how a perpetual calendar remembers February

Jaeger-LeCoultre · Master Ultra Thin Perpetual Calendar

The model in detail

Its complexity lies in calendar logic rather than the number of hands. The mechanism accounts for different month lengths and leap years. For a collector, that is an appealing idea: a small mechanical system retains rules we normally entrust to a phone.

There is an important qualification to the promise of running until 2100: continuous operation and correct initial setting are assumed. If the watch stops, its calendar needs resetting. Correction in 2100 is necessary because that centennial year is not a leap year under the Gregorian rule.

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The automatic calibre 868 runs inside a 39 mm case. An undisplayed price in the selected official regional listing is no reason to substitute an old figure or another currency: the manufacturer invites an enquiry. This is the selection’s collecting summit, rather than an exact budget reference.