How it work: This electronic pest repeller works through ultrasound, irritating the pest's brain and auditory nervous systems, so as to repel most types of pests away effectively. Effective for most pests indoor: install one pest repeller throughout each room for full coverage, repelling rodents and insects, like rats, bugs, cockroaches, spiders, ants, and more. Wide efficient coverage: the effective coverage of each pest repeller is up to 1600 square feet, and you can install these pest control repellers anywhere indoor there is pest activity, like garage, kitchen, attic, barn, RV. Easy to use: plug the pest control devices into outlets and they will start working when the blue night light comes on, just plug and play, no maintenance required, lasting 24/7. An easy and quiet way to deter pests: based on ultrasonic pest controlling tech, significantly dropped pest activity may take 3-4 weeks, no more spray and traps.