The ultimate in accuracy. This Howard Miller Accuwave DS wall clock automatically sets itself, and adjusts for Daylight Savings Time. Features an easy-to-read white dial with black Arabic numerals, black case, and glass crystal.This clock receives a radio signal from the cesium atomic clock, the most accurate clock in the world. Radio controlled clocks display Continental US Time Zones only. PLEASE NOTE: Radio signal interference may occur near electrical items or within some structures. Radio controlled, battery operated movement, automatically adjusts for Daylight Saving Time, and requires one AA sized battery (not included). Depth 1.75" (4 cm) Diameter 12.25" (31 cm)