The Pest-A-Cator plus has 2 technologies. Ultrasonic and electromagnetic which sends a pulsating signal that helps control rodents and roaches. Also the electromagnetic technology, the patented activity sends a pulsating signal throughout the wiring of the home and other structures. Direct plug-in feature is easy-to-use. Just plug into any 110V outlet. Safe around children and household pets (except hamsters, gerbils, and other rodent pets). Covers approximately 2000 sq ft.