What is a Chronograph watch?

– A Chronograph is a complication that works similarly to a stop watch, in that it is used to time events. Chronographs come in all different formats but traditional chronographs have a central chrono seconds hand and a two subdials – one each for the elapsed minutes and hours. Chronographs can usually time events up to 12 hours and can sometimes be as precise as reading a 100th of a second. Chronographs are usually activated by two pushers, which are found on either side of the main crown. The pusher at the 2 position starts and stops the chronograph, while the pusher at 4 is responsible for resetting it.