A Chronograph watch has 2 or 3 sub-dials with stopwatch functionality to keep track of seconds, minutes and hours.
An example of a Chronograph watch (Seiko SPC151P1) is illustrated below.
Activate the chronograph functionality by pressing the Start/Stop button as illustrated above. To pause simply press the same button again and to reset the chronograph functionality press the Reset button.
Each of the chronograph subdials measure how much time has elapsed since the timer was commenced.
Note that different brands and models may have different variations of chronograph functionality and not all have 2 buttons or measure all of the timeframes.
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