The Sonic MoleChaser Underground Rodent Repellant is a humane and environmentally friendly way to protect your garden or lawn from moles voles shrews and other destructive ground rodents. This lab-tested device repels pests by emitting an underground 300 Hz sonic pulse eliminating the need for traps and toxins. - Emits a 300 Hz sonic pulse every 15 seconds - 11 250 sq. ft. of coverage - Constructed from a single aluminum billet - Will not harm pets