Ultrasonic Insect Repellent: The Jucheng ultrasonic insect repellent adopts automatic frequency conversion ultrasonic technology, emits ultrasonic waves of 20~55 KHZ, stimulating the auditory and nervous systems of mosquitoes, cockroaches, mice, mites and other pests, effectively driving pests away from your home.Insect repellent safe for people and pets: The ultrasonic rat repellent operates at a frequency of 20-55 kHz, and frequencies above 20 kHz are inaudible to the human ear. As long as the repellent is not placed within the sensitive hearing range of cats and dogs, it will not harm your pets.Large Area Mouse Repellent: This mouse repellent can effectively prevent pests in an indoor area of 80 to 120 square meters and can be widely used in homes, offices, hotels, etc. We recommend installing one in each room due to the spread.Plug and Play Rodent Repellent: Simply plug in our repellent and it will start working when you notice the mist. This repellent should be installed 10-30 inches above the floor with no other obstructions within 1 meter. If you install the device in one room, it will not work in other rooms.What you get: Pack of 4 ultrasonic insect repellents.