Pest a Cator….Plug in rodent and insect repellent. Insect and Rodent Repellent. Covers up to 2000 square feet. Works behind walls and ceilings and can be used anywhere. Safe to use around all household animals except gerbils, hamsters and other rodent pets. Plus, the unique Pest-A-Cator activity will not adversely affect computers, telephones or other home appliances.Very easy to use, UL listed safe. This is NOT ultrasonic – ultrasonic s do not penetrate walls where pests hide.The Pest-A-Cator sends a pulsating signal throughout the wiring of homes and other structures. This silent pulse annoys insects and rodents driving them from behind walls, floors and ceilings where they hide and nest.