Easy to Use: Ultrasonic pest repeller plug into a power outlet; The ultrasonic repellent starts when the blue light turns on, repels many kinds of pests against rodents, hamsters, mice, fleas, ants, mosquitoes, flies, spiders, cockroaches, insects, rodents and bugs. Large Effective Coverage Area: The effective area of the pest repellent can reach 1600 sqm; Please put only one mouse repellent in each room because ultrasonic waves cannot penetrate walls and solid objects, 6-12 units are enough to repel pests in (depending on the severity of the pest infestation) Quiet and Effective: The ultrasonic repellent works with low-frequency ultrasonic waves, which are difficult for humans to hear. But very effective against rodents and pests, ultrasonic waves allow them to quickly leave your home! The principle of ultrasonic pest repeller: Through low-frequency ultrasonic waves, the brain and auditory nervous system of mice and pests are stimulated, to effectively expel most types of pests Less