CHRONOTHERMOSTAT ELECTRONIC DIGITAL WALL TO WALL WEEKLY PROGRAM FREE BATTERIES for heating and AIR CONDITIONING. General Features • Blue backlit display • Ultra-slim design! Only 19mm thick! • 3 temperature levels freely programmable + antifreeze • Daily scheduling free, 5 + 2 (Monday to Friday + Saturday and Sunday) or 7 / 7 (Monday-Sunday) • For heating and AIR CONDITIONING • Adjustable temperature differential • Function Party, Holiday, Override and fixed temperature • Temperature set to environment and ALWAYS VISIBLE • Battery Power • Battery change indicator • Wall mounting or back box three modules • Input for dialer