Product review (3 stars): Expensive but it works
This device is too expensive for what it is....but it seems to work.  Installed in our garage fridge just before we had a week of temps in single digits and below.  You can feel with your hand that the device heats the area housing the thermostat so that the compressor will kick on from time to time regardless of the outside temperature.  The freezer area has not thawed.  It works.