Glossary
The button on a chronograph case, separate from the crown, used to start, stop, and reset the stopwatch function.
Pusher shape, action, and placement are reference-specific, and a chronograph's pushers should operate smoothly with a feel consistent with the caliber inside. Pushers that feel loose, misaligned, or mismatched to the case can indicate case parts from different watches, or an aftermarket replacement.
Browse the full glossary, or look up a serial number in the registry.