I find that this device actually works as advertized when set to the right frequency range to target racoons and skunks. I was not certain if the motion detector would be triggered by a small animal such as a skunk though, so instead I just set the unit to be constantly ON at night. The critters seem to have stopped digging up my backyard lawn and switched to the front lawn now. Unfortunately the price of this device is too high to install one one each side of the house, so I am going to wait for a price drop or look for more cost effective solutions.