The Citizen Eco-Drive World Chronograph A-T is a radio-controlled perpetual calendar chronograph world timer with atomic timekeeping in 5 time zones (North America, the UK, Europe, Japan and China) and automatic time in 26 world cities. Specific functions also include a 1/20 second chronograph that measures up to 60 minutes, perpetual calendar, 12/24 hour time, day-date, alarm and power reserve indicator. This handsome timepiece is crafted in stainless steel with a patterned black dial, non-reflective sapphire crystal and a foldover clasp with hidden double push button. Additional details include a 43mm case and 200 meter water resistance. Citizen Eco-Drive is fueled by light, any light, so it never needs a battery. Combined with atomic timekeeping, it is the most accurate watch in the world.