I waited course before giving my opinion to not fool anyone. It is an efficient unit, provided to use it properly. You should know that ultrasound does not penetrate furniture, no matter in general. They can be compared to light: where it goes, as the ultra sounds. So if you have rodents behind a partition, no need to place the device outside of this one, even against everything, it does not. We must succeed in interposing IN the wall. At this point, it is very efficient. Counting days, and rodents normally leave. We had a rat who was walking behind the wall of the kitchen and into the false ceiling, very unpleasant ... For almost one week nothing, he left. I advise this purchase.
