Sporting a rotating slide rule bezel, the Citizen Skyhawk A-T stainless steel men's flight watch offers advanced timing functions and the latest technology. It's powered by Citizen's unique Eco-Drive, which absorbs sunlight and any artificial light through the crystal and dial to recharge the watch continuously. The fast-forward timekeeping features include time and calendar in 43 cities, thirty cities, three world time alarms, a 99-minute countdown timer, one-touch interchangeable analog/digital time, and 1/100-second chronograph that measures up to 24 hours. Besides sunlight, it can be safely charged by exposing it to a fluorescent desk lamp, with the dial (face) up and within about 8 inches or an incandescent lamp (regular light bulb) no closer than 20 inches. Never use a halogen lamp since the heat generated by it can cause damage to your watch. The most efficient and the quickest is in direct bright sunlight (not windowsill) and never on the dashboard of a car.