Glossary
Chronometer and COSC explained
chronometer COSC
A chronometer is a watch whose movement has passed a standard accuracy test. COSC is the well-known Swiss testing body. The label tells you about accuracy, not whether the watch is right for you.
What certification covers
COSC tests uncased movements for accuracy across positions and temperatures. Some brands run their own standards, which can be stricter or just different. Certification is about timekeeping, not design or how sturdy the bracelet is.
How much it should count
It's useful if you want proven precision out of the box. It doesn't matter much if you prefer vintage character or quartz accuracy. Treat it as a nice extra, not a reason to buy on its own.
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