Citizen introduced the ISO Certified Aqualand Eco-Drive to commemorate its revolution of the dive industry. Features include current depth display in digital & to 300 feet; measures depth & time of dive, max depth & duration of dive; dive log memory up to 20 dives; auto-start dive mode, and water temperature display & memory, among others. Featuring our Eco-Drive technology – powered by light, any light. Never needs a battery. Caliber number U107.