LUX Heating and Cooling Programmable Outlet Thermostat 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. Dimensions 3 In. W x 5-1/4 In. H, Pkg Qty 1, Package Type Clamshell