PestZilla Advanced Pest Repeller Device with Direct Plug-in with Night Light &ndash; Defends Against All Types of Insects and Rodents Removes all insects and rodents from your home without any harmful chemicals or sprays. Features Electromagnetic technology that blocks all pests from entering your home. Emits a mix of frequency waves to ensure pests do not get immune to the sounds. Completely inaudible to people and to home pets such as dogs, cats, birds, etc. Coverage area: 5,000 Sq. Ft. However for ultrasound it's recommended to get one unit for each room.