The A. Lange & Söhne Tourbograph “Pour le Mérite”, reference 702.025 and introduced in 2005, is a hand-wound platinum watch from Lange’s most elaborate group of timepieces. The “Pour le Mérite” designation marks a Lange watch that combines a fusée-and-chain transmission with a tourbillon. I could not confirm the full complication list and case dimensions from a single source, so they are not given here.

The fusée-and-chain mechanism keeps the force delivered to the movement constant as the mainspring unwinds, as in 18th-century marine chronometers, and Lange made it a feature of a few select models. The watch was produced in a very small run.

Collectors count the Tourbograph Pour le Mérite among Lange’s great watches and a defining example of modern German high watchmaking. The 2005 model is no longer produced; a Tourbograph Perpetual Pour le Mérite followed in 2017.