1. This Multi-functional Electronic Pest Repeller use the principle of ultrasonic wave and electromagnetic to interfere with pests.. 2. Ultrasonic have fixed frequency and variable frequency wave, customers can according to different environment switch different mode. 3. The electromagnetic will auto work and emit magnetic waves to enhance products driven effect, then the green light turns to red. 4. With a nightlight provides a soft light to avoid the total darkness in areas near the unit. 5. Best electromagnetic pest repeller Can be widely used in family, restaurants, supermarket, warehouse, office buildings etc which is unfavorable use medicine kill mouse 6. Non-toxic, Non-taste, out of the hearing range of humans and most household pets. 7. Effective range about 200 square meters. 8. Object: mouse, rat, mosquito, dust mite, bat, lizard, spider, cockroach, fly etc.