When plugged into a standard 120v outlet, the TC-3 will automatically turn power on and off to any device plugged into it.  On the TC-3, when the air temperature reaches approx. 35F it will turn on, and when it exceeds approx. 45F it will turn off the power.
Max rating: 1800 watts, 15 amps, 120V. Should be used with GFI outlets.