The Advanced Pest Repeller from The Big Cheese® uses a combination of swept ultrasound and electromagnetic action to drive rodent pests from the home. The unit is inaudible to humans, as well as cats and dogs. It is safe to use around children and it will not adversely affect electrical wiring or interfere with domestic appliances. Dual action ultrasonic and electromagnetic output pulses through wiring to reach nest sites within walls, ceilings and cavities.