Product review (5 stars): Cheap and effective gadget
A nice little gadget that I use to measure my Fridge temps in both the freezer and the main compartment. I purchased two of them and compared the reading between them, and as compared to a mechanical thermometer; they all agreed. I simply attached the sensor to the inside wall of the Fridge and threaded the wires through the rubber seals.

I don't see any good reason to buy an expensive wireless thermometers---just in order to avoid the wiring. For me, that's a matter of aesthetics and not of functionality.