This is a unique Lang & Heyne* watch that borrows elements from the brand’s Konrad and Friedrich II and III watches. It features a 39.2mm platinum case with a white enamel dial and a dead beat complication. Underpinning it is a manual wind calibre created to custom specifications featuring a one-second remontoir and a free balance with a balance cock hand-engraved with a floral motif. The watch wears the serial number 00, a reference to its special status.
A remontoire is delicate - and it’s hard to make a delicate system reliable. Given its complexity, one might argue, that the gains in precision are too small. And then it typically adversely affects the fragility of the system to position it so as to see it working through a caseback window, which limits its appeal for some.
This niche idea is that of giving constant force to the escapement, long a challenge to mechanical watchmaking seeing as the energy from the main spring, inevitably, gradually decreases as it relaxes from its fully-wound, maximum force state. So, John Harrison, he of the world-changing marine chronometer, came up with the remontoire back in the 1760s.
It’s clever because when its own spring - or, in larger mechanisms, maybe a weight - reaches the end of its power, its re-winding is automatically triggered - at an interval of any time between one second and one hour - and it’s this frequent re-winding that adds to accuracy because it averages out any changes in the force of the remontoire itself.