BEST ULTRASONIC PEST REPELLERS, DRIVE THE PEST AWAY QUIET AND EFFECTIVE - If you're considering a non-chemical approach to pest reject, we recommend the Ultrasonic Pest Repellers are devices that emit a consistent noise at a frequency that is too high for humans to hear. These sound waves are designed to distract, annoy, and deter common household pests such as roach, spiders, mosquitoes, ants and rodents. Intelligent multi-frequency ultrasonic conversion systems make pests nowhere to hide. PROTECT YOUR FAMILY IN A HEALTHY AND PEACEFUL WAY - pest repellents are safer than traditional mosquito repellents. Many people are naturally worried about the safety of their pets when using an insect repellents device. Studies found that cats and dogs, although can hear the waves, ultrasonic sound is inaudible to humans and household pets. No poison, smell, and chemicals, significantly safe and harmless for kids, pregnant women, and pets. HOW TO USE AN ULTRASONIC REPELLER IN YOUR HOME - Pest repellents are simple to use. All you do is plug pest repellent ultrasonic in an electrical outlet and it will start to repel the pests when the blue night light is on. The repeller should be placed in a location where its noise will not be affected by walls and furniture. It is recommended to install this pest repeller between 30-50 inches away from the floor for flying pests and 10-30 inches from the ground for crawling pests. 360PROECT YOUR HOME WITH NO DEAD ZONE - The effective coverage of each pest control is up to 1600 square feet. Since ultrasonic sound can not penetrate walls and solid objects, ONE ROOM ONE UNIT IS RECOMMENDED. 360 degree protect your home with no dead zone. It's widely used in homes, warehouses, offices, restaurants, supermarkets, hospitals, granary, etc.