A Self Charging Solar Power system drives the new Casio W-S210 Series; a new eco-friendly timepiece that graphs Tidal movements & Moon Phases and is 100M Water Resistant. The unique power system eliminates the need for battery changes and is strong enough to power a multitude of additional functions such as 48-city World Time, 1/100th Second Chronograph, 5 Daily Alarms and more. Available in resin or stainless steel bands, this new tide tracker is sure to please on your next marine adventure.