With bold design and superior accuracy, Citizen AT watches synchronize to an atomic clock with a margin of error of just one second in 100,000 years 1/20 Second Chronograph Measures up to 60 Minutes, Perpetual Calendar, 12/24 Hour Time, Power Reserve Indicator, Day/Date Silver-Tone Stainless Steel Anti-Reflective Sapphire Crystal 200 Meters Water Resistant and 5 Year Limited Warranty Kindly refer the troubleshooting video for changing the date and time.