This quartz clock automatically receives and synchronizes to the WWVB time signal in the U.S. Just install the battery, set your time zone, and the clock takes care of itself. The illuminated display shows hour, minutes and seconds. It has a time alarm with snooze.The size is relatively small at 2.63” (W) x 0.86” (D) x 3.63” (H). Weight is 5 oz. Power is from 1 AAA Battery which is included. SW 1 lb.