Your watch can switch between its main-dial and sub-dial.
Both the conditions for DST (Daylight Saving Time) set in the main-dial and the conditions for DST (Daylight Saving Time) set in the sub-dial switch.
This comes in handy in the following situations.
Matching the main-dial to the time for the time zone set in the sub-dial
To use your watch, adjust the main-dial to the local time, and then, after returning home, restore the main-dial to the sub-dial’s Japan Standard Time
How to switch the main-dial and sub-dial
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Press and hold buttons A and B at the same time (1 second)
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Press buttons A and B at the same time for 1 second
Main-dial: time in Tokyo
Sub-dial: time in New York
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Main-dial: time in New York
Sub-dial: time in Tokyo
The seconds hand indicates the time zone for the main-dial that was switched. The multi-function indicator hand indicates the setting status for DST (Daylight Saving Time) of the main-dial that was switched.
Afterward, the main-dial’s hour and minute hands, sub-dial, and date switch.
Finally, the seconds hand returns to the time display, and the multi-function indicator hand returns to the day of the week display (or the charging status display).
The buttons cannot be operated while the hour and minute hands, multi-function indicator hand, or sub-dial is moving.