Embodying the spirit of adventure in the air, on land or at sea, Promaster watches live up to the values of functionality, durability, and safety while respecting the planet its designed to explore. Using radio control, this technology automatically updates the time and date of your watch based on a time signal from an atomic clock with a margin of error of one second every 100,000 years. Time signals are received from transmitters, or atomic clocks, in four different regions: Europe, the United States, China, and Japan.