Many watches today have a "hack seconds" feature. When the crown is pulled out to adjust the time, the seconds will stop. This allows accurate synchronization with another clock. On most hack movements, when the crown is pulled out, a lever is moved which contacts the rim of the balance, which causes the movement to stop.
What Does Hack Second Hand or Hacking Function Mean? Print
Modified on: Fri, 28 Nov, 2014 at 10:18 PM
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