The second hand doesn't stop when setting the time

What does hacking seconds mean?

Hacking seconds means that the second hand stops as soon as you pull the crown out to the position for setting the time.

This lets you set the time especially precisely – for example, to a reference time or a time server.

With movements that don't have hacking seconds, the second hand keeps running while you set the time. You can still set the time, but not quite as precisely to the second.

Whether your watch has hacking seconds depends on the movement fitted.