Hacking Seconds
A function that stops the seconds hand when the crown is pulled to the time-setting position, allowing precise synchronisation.
Also known as: stop seconds, seconds hacking, hack seconds, hacking function
Definition
Hacking seconds is a setting feature that stops the running seconds indication when the crown is pulled to the time-setting position. In a mechanical movement, a small stop lever commonly contacts the balance wheel or otherwise interrupts the oscillator, allowing the wearer to hold the seconds hand at a chosen point and restart it when the crown is pushed back. The feature is also called stop seconds. It is useful for synchronising a watch closely to a reference time.
Why it matters
Hacking seconds makes accurate setting much easier, particularly when synchronising multiple watches or matching an external time signal. Its presence is a practical usability feature rather than a measure of movement accuracy.