AC plug; includes button battery backup for time and alarm settings.
Projection Alarm Clock A unique “ascending” alarm increases in frequency to rouse stubborn sleepers. Unlike illegible, inaccurate projection clocks, The Best model casts the time and outdoor temperature/humidity (from an included remote sensor) in large, easy-to-read red digits up to 7' onto a ceiling or wall.) The easiest clock to set up, it can be customized to one of five display options (indoor temperature/ humidity, outdoor temperature/humidity, alarm time and on/off status, day/ month/date, or scroll through all), four brightness settings, and its large backlit LCD panel can be programmed to dim automatically at preset times.