With A.Lange & Söhne Guarantee Certificate dated 5 September 1996 and stamped by Wempe, Bremen, operating instructions and original fitted black leather presentation box.
The present watch is number 50 of the strictly limited series of 50 examples of the Lange Tourbillon "Pour le Mérite" in platinum, in production from 1994 to 1998.
Lange's Tourbillon "Pour le Mérite", another example of the company's complex and exclusive timepieces, incorporates a number of fascinating technical details never seen before in a wristwatch, among them the going train driven with a chain fusée. This complicated mechanism optimises the rate accuracy of the watch and is visible through an aperture in the movement plate. A highly sophisticated planetary gearing system keeps the power to the going train steady even while the watch is being wound.
It appears that the "Pour le Mérite" Tourbillon is one of only two wristwatches known today fitted with a chain and fusée for the power equalization. The second model is its even more complicated twin, the "Tourbograph Pour le Mérite" wristwatch with tourbillon and split seconds chronograph, introduced into the market in 2006.
The tourbillon mechanism also serves the purpose of improving rate accuracy by offsetting the disruptive effect of gravity. The rotating cage is suspended by two pivots between two diamond endstones. It turns around its own axis once a minute and can be precisely balanced with small counterweights.
All parts of the watch are finished by hand and every surface is decorated. Consequently, the completion of each of these masterpieces required several months.