You never need to change the battery and the Casio Atomic watch receives a time calibration signal transmitted from Fort Collins, Colorado.  And that means that it will give the correct time probably into your great-grandchild's lifetime, or longer.

Encased in black steel with matching black steel band, this G-Shock Solar Atomic timepiece has an hourly time signal, auto calendar, digital display, auto backlight, 4 alarms with 1 snooze alarm, world time, a 1/100-second stop watch, and it is shock-resistant plus water resistant to approximately a 650-ft. depth.

The case measures 45mm x 15mm thick and the watch comes with a one-year original manufacturer's warranty.

Shipping weight: 2 lb.