For use only with portable air conditioners and space heaters that have automatic restart cooling or heating operation after power reconnection. This model offers the convenience of 5-2 day programming so different programs for weekdays and weekends can be created. Preprogrammed with 4 periods per day. Unit plugs into a standard 120V household outlet (with ground). Features include a setting range of 45 deg. F. to 90 deg. F., temporary temperature override, patented Lux Speed Dial for easy programming, armchair programmable, positive On/Off switch, battery-free memory storage. Two 1.5V G13 alkaline button cell batteries are included for maintaining the clock. 5.25" H. x 3" W.