Hacking tourbillon
The hacking tourbillon makes it possible to stop the tourbillon at any time, with the balance and cage in any position. Until now, for IWC tourbillon watches, pulling out the crown would stop the hour and minute hands, but the gear train would continue to run. Now, the balance, and thus the entire gear train including all hands, is also stopped. When the crown is pulled out, the mechanism is stopped by two levers that grip the balance rim like a set of pliers.
