Heat Control Features ● Controls the output of the heating equipment in 3 stages ● Controls heater output according to the animal being kept ● Controls the heater output to an optimal level for the cage size, even with an overpowered heater ● Controls heater output according to seasonal changes and ambient temperature fluctuations ● By controlling the output, it reduces the number of times the heater (such as a heat bulb) turns on and off by the thermostat *This product is not a thermostat.