Motion activated animal deterrent. Jack Ultrasonic Animal Repeller is designed to protect your garden, backyard or pond from uninvited animal visitors like dogs, cats and rodents. Safe and humane, it combines a sophisticated Passive Infrared (PIR) Detection System that detects movement and triggers short bursts of powerful ultrasonic sound waves. Simply stake into the ground or mount on walls and it’s ready to go to work (up to 45 square meter coverage or up to 8m distance). Battery operated: requires 3 x AA batteries (not included in the pack).