An
automatic watch winds itself with the motion of your wrist, so you'll
never need to change the battery. If the watch is worn daily, Seiko’s
automatic mechanism will wind the mainspring automatically through
normal wrist movement.
To initially start your watch, you are required to swing your watch from
side to side in a horizontal arc for about 30 seconds. Once adjusted to
your local time, you can wear it on your wrist and the movement's
mainspring will wound automatically through normal wrist movement. If
you have left the watch un-touch for a few days, it will stop. Repeat
the above steps again to restart your watch.