Seiko Automatic watches with caliber number 7S36  power themselves by the motion of your body. Contrary to the Seiko kinetic watch collection, there is an automatic winding mechanism but then it does not need any hacking or hand winding to get the watch started. Automatic movements are a subset of mechanical movements that, when worn daily, do not need to be wound. Every time the watch is worn, an oscillating weight in the movement winds the mainspring, thus ensuring the mainspring remains fully wound. The Seiko automatic watch needs just to be set at the correct time and given a shake to charge up and gives you the most accurate and reliable time with a power reserve of up to 40 hours.