A. Lange & Söhne 1815 Rattrapante Perpetual Calendar

The A. Lange & Söhne 1815 Rattrapante Perpetual Calendar, reference 421.056FE, combines a perpetual calendar and split-seconds chronograph in a 41.9 mm case. The 18-carat white gold model is a limited edition of 100 pieces. The case measures 14.7 mm high, with 20 mm between the lugs. The case has a see-through back and a water-resistance rating of 30 metres. Manual-winding calibre L101.1 contains 631 parts, runs for 42 hours and beats at 21,600 semi-oscillations per hour. The dark brown alligator leather strap fastens with an 18-carat white gold folding clasp. The dial is made of solid 18-carat pink gold and carries analogue date, day-of-week and moon-phase displays, plus a power-reserve indicator.