The improvement comes with an improved low frequency waves and is much more safer to humans and pets that won't disturb your sleep during night time. It includes sound generators that mimics predator to repel fox and racoons through bionic waves. For highly infested area, use 5 units of pest repellent to effectively eradicate insects and pests. This is an advantage flea treatment for cats and dogs. CLEAN AND MESS FREEUnlike traditional pest defender techniques where pests are killed, this electronic pest repeller repels pests and forces them to find their way out of your house. NEWEST CHIPS TECHNOLOGY This indoor complement emits invisible electromagnetic waves to expel insects, mice, rats, mosquitoes, ants, spiders, cockroaches, and other insects. Without having to kill them. Please note that our ultrasonic repellents work between 3 and 4 weeks to make an effect depending on the amount of infestation. Then we can say goodbye to pests and mice. WIDE EFFECTIVE COVERAGE The Insect & Rodent Repellent is effective in an indoor area up to 1600 sq. ft. It’s widely used in homes, warehouses, offices, gardens, hotels, etc. We recommend you to install one for each room because the ultrasound cannot penetrate walls and solid objects. But for areas with serious pests, we suggest install 2 or more devices for other room. They aren't effective for other rooms if you install device at one room.