A. Lange & Söhne Lange 1 Tourbillon Perpetual Calendar "25th Anniversary"

The A. Lange & Söhne Lange 1 Tourbillon Perpetual Calendar "25th Anniversary", reference 720.066FE, has a perpetual calendar, a tourbillon and an 18-carat white gold case. This limited edition of 25 pieces measures 41.9 mm in diameter and 12.2 mm in height. The case has 22 mm between the lugs and a 30 metre water-resistance rating. The dial is crafted from solid silver, with outsize date, weekday, moon-phase and day/night displays. Self-winding calibre L082.1 contains 624 parts, runs at 21,600 semi-oscillations per hour and has a 50-hour power reserve. A blue alligator leather strap with grey stitching has an 18-carat white gold folding clasp. The tourbillon is visible through a see-through case back.