Atomic Digital Alarm Clock uses the same technology NASA employs to tell time, Atomic clocks wirelessly synchronize with the National Institute of Standards and Technology's atomic clock in Boulder, Colorado. In addition to daily confirming the time, these clocks automatically adjust for Daylight Saving Time and run up to two years on a single AA battery. No wires, no worries, and no more excuses for being late. Features Picture frame styling Constant calendar Inside temperature Alarm clock with repeat snooze LCD gray display with black numbers 3 x 5.