Help repel pests， without the mess! Bell + Howell’s Electromagnetic Ultrasonic Pest Repeller is a unique device that is designed to drive away ants， spiders， mice， rats， cockroaches and other rodents only using ultrasonic sound waves and electromagnetic waves. That means no unpleasant odors or dangerous chemicals to inhale and no messy， toxic sprays that may put your pet in danger. It works through wiring within walls sending a signal to deter pests. And the outlet feature on the side creates another spot for you to plug other electronics in while the Pest Repeller is plugged in! So， say “bye bye” to unwanted visitors by using Bill + Howell’s unique Ultrasonic Pest Repellers!