Product review (5 stars): No frills and it works.
I bought this to complete a kegging system project using a cheaper scratch and dent apartment size refrigerator from one of the big box stores.  The problem I was having was that the keg would keep icing up due to the air not circulating like it would in a better quality refrigerator.  This solved the problem.  I placed the sensor at the base of the keg since settling of the cool air seemed to be what was causing my icing.  IT WORKED.  An additional benefit could be the energy savings with the refrigerator being completely powered down running less.  The temperature setting is accurate.  Now we have ice cold beer without the ice.

The capillary tube is very thin so it doesn't effect the seal of the door.  It might take some creativity mounting of the controller and running of the capillary tube.  It does come with a chain to hang it or keyhole slots on the back.  I have a heavy duty magnetic coat hook that I stuck on the side of the refrigerator and hung the control unit from it.