Refers to the Seiko line of Kinetic watches. This innovative technology has a quartz movement that does not use a battery. Movement of your wrist charges a very efficient capacitor which powers the quartz movement. Once the capacitor is fully charged, mens models will store energy for 724 days without being worn. Ladies models store energy for 3-7 days. Of course, if the watch is worn every day the capacitor is continually recharged. The watch alerts you to a low capacitor charge when the seconds hand starts to move in two second intervals. For more information, click to go to Seiko's Internet Site.