DuraHeat® FA1210 External In-Line Thermostat for Kerosene Forced Air HeatersTurn your kerosene forced air heater into a thermostatically controlled model in seconds. External thermostat for most kerosene forced air heater brands. Works with most brands, including DuraHeat and Desa models. Provides easy termperature adjustment from 10 to 100 degrees F. External in line thermostat Works with most brands, including DuraHeat and Desa models Provides easy termperature adjustment from 10 to 100 degrees F Plugs into 120V grounded