Citizen eco drive technology with radio controlled atomic timekeeping makes it the most accurate watch in the world this analog 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 stainless steel with black dial and bezel 43mm case and 200m wrmovement eco drive h145date displaycase stainless steelstrap silver tone stainless steelwater resistant 200 metres