Rodent Repellent Plug-in Deterrent Emits Ultrasound Waves and LED Strobe Lights. ultrasonic repellers are devices that emit high-frequency sound waves to deter rodents and pests from entering a space. These devices are advertised as a humane and chemical-free solution. They work by emitting sound waves that are above the hearing range of humans

•  4 in 1 design, the continuous alternating frequency of ultrasonic and electromagnetic waves is capable of effectively repelling squirrels, rats, mice, gerbils, jerboas and more rodents by effecting their nerve auditory systems.
• The Careland Ultrasonic Pest Repeller features a mix of highly-effective ultrasonic frequencies, being extremely irritating to rodents and pests thus causing them to scramble to find a peaceful area outside of the home.
• There are 4 function switches: TEST, ULTRA, TRAN, DUO and 9 LED strobe lights which disturb rodents’ eyesight in dark environment.
• It is a rodent repellent for indoor use that combines advanced technology and humanitarianism. It is cheaper  than expensive pest control companies and other pest control methods.
• low Power Consumption, no battery required . makes a great fit for hallways ,basement ,attics & Motorhome