In a race against time
The upper button in the right-hand case flank starts and stops the chronograph hands, the lower one resets them to zero. The flyback function is activated when the lower button is pressed while the chronograph hands are running. This allows the hands to be stopped, reset to zero and restarted for a new measurement in one single step. When the button in the left-hand case flank is actuated, the rattrapante hands will stop to display a first intermediate time. This action reveals the rattrapante hands because previously, they were hidden beneath the running chronograph hands. When the button is pressed again, the rattrapante hands catch up with the chronograph hands and run synchronously with them.