What are the precision tolerances for a Herc Mechanical watch?
To earn the title of chronometer, the mechanical movement’s average daily variation in rate must be between -4/+6 seconds per day, or a precision of 99.99%, the highest precision attainable by a mechanical movement. The precision of a mechanical movement depends on the individual habits of the wearer and can therefore vary. A qualified Herc watchmaker can adjust the precision of a watch to within the Herc tolerances, which are from -1 to +6 seconds per day.
