Lange 31 - A Lange & Sohne

POWER RESERVE: 744 HOURS

The LANGE 31 is the world’s first mechanical wristwatch with a power reserve of 31 days and a patented constant-force escapement. To deliver a power reserve of this magnitude, the movement must be able to store a large amount of energy. This task is handled by two mainsprings that are both 1850 millimetres long – about ten times as long as in mechanical wristwatches with a conventional power reserve.