mondaine stop2go Instruction Booklet page 8

Reset of the second hand – to stop at 12 o'clock position
In case the second hand is misaligned and does not stop at 12 o'clock push
the switch for 3 seconds to activate the correction mode.
Turn the switch element anti-clockwise (do not pull out the switch – it must
remain in zero position). The second hand starts moving forward.
For quick setting keep it in the turned position, for fine tuning just give short
individual impulses on the switch. When the second hand has arrived
at 12 o'clock push on the switch to confirm the standard mode.