Stop seconds Mechanism that stops the balance wheel and thus the movement of the seconds hand when the crown is pulled. This allows a watch to be precisely synchronised with an external time signal.

For the first time ever, the patented | stop seconds mechanism for the tourbillon allows timepieces with this complication to be set precisely to the second. The mechanism is activated when the crown is pulled, causing a V-shaped arresting spring to swing towards the circumference of the balance. As soon as the arresting spring contacts the balance-wheel rim or a post of the tourbillon cage, the balance and the cage are halted. The momentary positions of the posts and balance make no difference. If one of the posts lies between the arms of the arresting spring, both of its arms will contact the balance. If a post blocks the advance of a spring arm, the other arm will come to rest on the balance-wheel rim.