The Raxxess 12VDC On/Off Thermostat ensures quick cooling of your devices by activating the fans when the temperature of your system rises above 85deg. F (29.4deg. C) and turning them off when it falls below 75deg. F (23.9deg. C). This simple but effective thermostat automatically shuts down the fans when the system is not being used, thereby saving power. In addition, the thermostat features 2 outputs for controlling up to 2 fan panels.