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Measuring 39mm x 9.2mm and offered in pink gold or steel, the Master Ultra Thin Perpetual Calendar is the epitome of refinement and contemporary elegance. Its finely balanced dial features a moon-phase display at 12 o’clock and calendar indications on three sub-dials – each slightly recessed to add a subtle note of visual complexity. The movement, Jaeger-LeCoultre Calibre 868, was entirely developed and produced in-house and features fine-watchmaking decoration such as Côte de Genève striping, perlage (circular graining), and polished and bevelled edges. Through the transparent sapphire case-back, an open-worked pink gold winding rotor allows a clear view of the movement. A highly complex mechanism, the perpetual calendar takes into account the irregularities of the calendar, automatically adjusting for months of different lengths and for leap years. So long as it is kept wound, a perpetual calendar needs no adjustment until 2100 and then not for another 400 years.
References: Steel Q130842J; Pink Gold Q1302520