YHMALL Plug In Ultrasonic Pest Repeller (2 pack) - Electronic Pest Control Mosquito Repellent for Squirrel Rodent, Insects, Mice, Bugs Indoor and Outdoor. Protection for Adults & Kids (2a) The latest chip technology: The upgraded ultrastechnologyonic mosquito repellent uses the latest chip technology to drive pests and rodents out of their homes. The latest chips enhance the frequency and intensity of ultrasound to better stimulate or interfere with the pest's nervous system. For best results: it is recommended that you install each room. No mosquitoes in the bedroom will help your sleep. Easy to use: The tiny, compact design makes it a portable plug-and-play product. Just plug in the socket and let low frequency sound waves do all the work for you. Ultrasound causes confusion, convulsions and even death, forcing the pests to move away. Say goodbye to poisons and chemicals: The pest repellent does not use dangerous and harmful poisons. Just plug in and enjoy. No battery needed! It is useful for all kinds of pests: The ultrasonic insect killer can deal with various pests including squirrels, mosquitoes and mice, flies, cockroaches, spiders, fleas, etc. The sound is not detected by the ear and therefore does not interfere with or stimulate humans, cats and dogs.