Ultrasonic Pest Repeller (Pack of 4) with Night Light to Eliminate All Insects and Rodents like Mosquito, Rats, Mice, Cockroach, Fly, Ant, Roaches & Spiders. UPGRADED VERSION - This is our second-generation ultrasonic pest control product. It has a higher output power, a wider controlling range. It can be effective as a large range as 120 square meters. This product has already help millions users solve pest problem. CREATES A PEST BARRIER - The Pest Repeller emits 20~55KHZ ultrasonic. It can disorder insects and pests endocrine system and physiological function. Thus it causes them to scramble to find a peaceful area, and forces them to leave your home. The ultrasonic that sent out from this machine is far away from hearing range of human being. It will not do any harm to human being and pets. Also it will not have effect on house machine. EASY TO USE - Simply plug directly to 110V power socket and as long as the LED light is lit, pests such as rats, mice , ants, fleas, roaches, mosquito, etc.. will keep away from your home. With our product you can do pest control by yourself.