product description:1. Dual-chip technology: This ultrasonic insect repellent uses dual-chips to make a more powerful sound. This ultrasonic frequency range stimulates and interferes with the brain and auditory nervous system to quickly and effectively repel most types of pests.2. Humanized ADN Efficiency: Uses safe and effective technology to extremely irritate rodents and insects, causing them to escape from your home. Depending on the severity of the infestation, typical results may take 2-3 weeks. Ultrasonic frequencies are inaudible to humans and safe for children and pets.3. Simple to use: Plug the ultrasonic repellent into any standard socket, then the ultrasonic repellent will emit strong ultrasonic waves to drive the pests away from your home4. Eco-Friendly Solution: Unlike glue traps, mousetraps or cockroach motels - all of which kill bugs and leave a messy cleanup - our ultrasonics won't cause harm or leave nasty dead insects or rodents behind for you to handle.5. Wide effective coverage: This animal repeller indoor ultrasonic is widely used in homes, warehouses, offices, gardens, hotels, etc. Since ultrasonic waves cannot penetrate walls and solid objects, it is recommended that you install one for each room. But for areas with severe threats, we recommend installing 2 or more pest repellers.