【Ultrasonic Mosquito Repeller】 - This is our advanced version. Using the principle of ultrasound, the frequency is modified to stimulate the auditory system of mosquitoes and other harmful insects, causing an unbearable and uncomfortable feeling. 【Wide Coverage】 - Each electronic ultrasonic mosquito repellent can effectively cover an area of up to 80 to 120 square meters. However, ultrasound cannot penetrate walls. We recommend using at least one mosquito repellent per room. This ultrasonic mosquito repellent is perfect for homes, offices, garages, attics, basements, warehouses, and greenhouses. 【Easy to Use】- Simply plug the ultrasonic mosquito repellent into a power outlet. Make sure to install it vertically, 30 to 120 cm from the ground. 【Eco-Friendly and Safe】- Ultrasonic waves only work on pests and rodents, and are completely harmless to humans and pets. No radiation, no chemicals, no smell, no noise. 【Effective Working Time】- Ultrasonic pest control usually takes 3 to 4 weeks