This is a split-seconds chronograph pocket watch. The split-seconds, or rattrapante, is a complication that allows you to time two events that start at the same time, but which may have different durations. Everything is activated via the pusher at noon: the two hands start their course at the same time, then by a simple press of the other pusher, one of the hands will stop.
Press again and it will allow the hand to catch up with the one who continues to race. When we look closely at the scales, we understand that the hands go around the dial in 30 seconds and that the minutes of the totalizer at noon are divided in two.
A small invisible detail: the beautiful movement of this timepiece beats at 36,000 vibrations and includes a tiny compartment that contains spare parts of the movement, if ever repairing is necessary. A detail we really love.