Complication
Chronograph
A stopwatch built into the watch.
What it does
Times events independently of the running seconds using pushers — usually one to start/stop and one to reset. Elapsed minutes and hours accumulate on sub-dials. A flyback chronograph resets and restarts in one press; a rattrapante (split-seconds) times two events at once.
How to read it
The central sweep hand shows elapsed seconds; the sub-dials count elapsed minutes and hours. The small running-seconds sub-dial keeps ticking while the chronograph is stopped.
Impact on value
Positive — chronographs are mechanically complex and highly collectible (e.g. Daytona, Speedmaster).
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