The Honeywell horizontal digital non-programmable thermostat provides simple control over your heating and cooling system. Simply set your preferred temperature on an easily accessible and user-friendly interface. Advanced temperature monitoring minimizes temperature swings and ensures absolute comfort. In the event of a power outage, the RTH111B will also remember your previous temperature settings. This thermostat features a broad compatibility range that covers single-stage heating/cooling systems, heating, cooling, heat pumps without backup heat, mill volt, pellet stoves and fireplaces.