Gents Citizen Eco-Drive watch. Radio-controlled atomic timekeeping makes this the most accurate watch in the world. This analogue world timer provides atomic timekeeping in 5 time zones and automatic time in 26 world time zones. Perpetual calendar, date, and non-reflective sapphire crystal. Steel rose gold tone. Leather strap Case diameter: 43 mm. Water resistant to 100m. Fuelled by light, any light. A watch that never needs a battery. Case diameter: 42 mm. Water resistant 100m. 5 year manufacturers guarantee.