Ultrasound Repellent - This is our advanced version. Using ultrasound theory, change frequency in order to stimulate the hearing system of mosquito and other pests, make them unbearable and feel uncomfortable. Easy to use - This machine should be instalLED 80-120 centimeters from the ground. And vertical to the ground and plug into the socket. Commonly used in homes, warehouses, shops, hotels, hospitals, offices, etc. Large areas may require more than one unit. Large Coverage Area - Each electronic ultrasonic repellent is effective for a large area up to 800-1300ft. Please note that ultrasonic waves cannot pass through walls. While our pest repellent works well, if you have a large infestation, we recommend placing our insect repellant in every room. Environmental and -Friendly - The product is non-toxic and environmentally friendly, our repellent is 100% safe and effective, the ultrasonic frequency emitted by this machine is inaudible to human beings and pets . Safe for , family and pets. However, if you have a hamster pet at home, do not use this ultrasonic repellant. Product Do you have rodents in your home? Don't want to use poison, chemicals or dangerous traps? Why not choose us? Rodent Repellent, Unlike a mousetrap, or chemicals, the ultrasonic device is efficient, environmentally friendly and completely risk free. Feature: Environmental friendly non-toxic 1, No chemicals and sprays, will not hurt your pets. 2, No noise, will not bore you. 3, No radiation, . 4, Easy to use, just plug it into the outlet. Parameter: Ultrasonic frequency: 22 ~ 65KHZ Input voltage: AC90V ~ 250V / 50Hz ~ 60Hz Power: 5-6W Effective coverage area: About 80-120 square meters Note: 1) The mechine should be instalLED 80 ~ 120cm from the ground and should be vertical to the ground and connected to the outlet (best effect). 2) One unit for each room is recommended for the best result, because the solid like wall, furniture and so on, will weaken the effect of ultrasonic wave. 3) Usually, it may take 1 ~ 3 weeks to notice the results. The number of pests and insects may increase in the first few days. In a few days of use, it is the normal phenomenon which increases the activity of insects. The pest controller will expel the pests after a certain period of time. Package: 4 * Ultrasonic Parasite Repellent 1 * User Manual