"Pour le Mérite" The hallmark "Pour le Mérite" relates to the highest German order of merit for exceptional scientific - and later also artistic - achievements. It was inspired by Alexander von Humboldt and instituted in 1842 by Frederick William IV. Lange uses it as an attestation and endorsement of its most eminent movements.

Fusee-and-chain transmission An original, early drive system in a spring-powered watch. It assures that the going train is driven with the same moment, or torque, regardless of the state of wind of the spring barrel. It improves the accuracy of the watch.

Double rattrapante Beyond the simple "stop watch" function, a rattrapante chronograph also allows lap-time measurements, time comparisons, and the determination of the fastest or slowest of several laps. With conventional rattrapante chronographs, these measurements are confined to the seconds scale and thus limited to a duration of 60 seconds. The double rattrapante mechanism developed by Lange has an additional rattrapante hand for the minute counter. This makes it possible for the first time to meaningfully exploit the rattrapante functions - for events that last up to 30 minutes.

Power-reserve indicator The power-reserve indicator displays the state of wind of the mainspring. It reminds the owner that the movement must be rewound again before it stops. Often called "UP-and-DOWN display" by Lange.

With its TOURBOGRAPH | "Pour le Mérite", Lange tested the limits of mechanical feasibility. The first glance at the movement already reveals two marvels from the high-end realm of complications: the tourbillon and the chronograph with the | rattrapante function. But what makes this timepiece really inimitable is concealed in the depths of its movement: the | fusée-and-chain transmission. Thus, together with the tourbillon, the TOURBOGRAPH unites the two most complex inventions for the optimisation of the rate stability of a mechanical watch. All displays of the watch are visible at a glance: hours, minutes, | power reserve, 30-minute counter. The superimposed, delicate sweep hands can be used to additively time events that last as long as 30 minutes and stop any number of lap times to one-sixth of a second. The classic design of this timepiece is based on harmonious proportions. Its appealing case, currently available exclusively in platinum, has a diameter of 41.2 mm and a height of 14.3 mm. The solid-silver dial has an aperture at 6 o'clock that reveals the fascinating motion of the tourbillon. The TOURBOGRAPH commemorates the 15th anniversary of the reinstated manufactory on 7 December 2005. It is of such daunting complexity that it will take Lange's master watchmakers until the end of 2006 to complete the first exemplars. Thereafter, only about one of these timepieces will leave the manufactory per month. Overall, the edition is limited to 101 watches.