Features: * For 24-volt heating and air conditioning systems * Low voltage control of gas or oil heating and cooling equipment * Bimetal temperature sensor * Snap acting switch (magnetic switch) does not require leveling and is mercury-free * Simple, worry-free operation * Compatible with single stage heating and cooling, furnace (warm air), central air conditioning, hot water, steam or gravity and gas fireplaces What"s In The Box: * Honeywell CT31A Heat/Cool Thermostat