King Electric ATMOS1-B Programmable Bluetooth Thermostat, White Programmable with atoms iPhone app (Bluetooth connectivity). program 4 or 6 time periods for maximum flexibility Battery powered. Large back-lit buttons allow easy adjustment & programming Etl listed. Electronic sensing for accurate temperature control (+/- 1F) Temperature range 41F - 90F (5C - 32C). 16 amp at 208/240 volts For use on baseboard, fan forced & radiant electric heaters. Limited 3-year warranty