The powerful sound waves generated by the transducers of the repellers are within the hearing range of many pests, and cause them pain and discomfort. Sometimes, the pests will leave the area being protected immediately,
and at other times it will take as long as four to six weeks before there is a significant reduction in infestation.
The transducers are quiet. If you cannot hear them, do not think that the unit is not
working. You cannot hear ultrasound. It takes three to six weeks for the system to have its desired effect on the Rodents.