Automatic frequency conversion technology: Ultrasonic Pest Repeller uses the latest automatic frequency conversion technology to generate different ultrasonic bands and constantly change the frequency, so that pests and mice cannot develop immunity or adaptability to insect repellent. The insect repellent is easy to install and plug in. The effect lasts 3-4 weeks. The ultrasonic repeller is ideal for homes, offices, garages, attics, basements, warehouses, greenhouses, gardens, hotels, etc. Wide Coverage Area: Each ultrasonic insect repellent has an effective range of up to 1600 square feet. It is recommended that this ultrasonic insect repellent be installed vertically 32-47 inches from the floor, and having an ultrasonic insect repellent in every room will help you achieve the best results. Thanks to the latest ultrasonic technology, you can get rid of the pest in a simple and easy way. No chemicals, non-toxic, no smell and noise. These pest repellents are suitable for kitchen,