P3 International P7901 Mole Chaser Gets rid of moles, voles, gophers, shrews & other burrowing rodents Made of sturdy, high-impact materials Penetrating sonic pulses of 300Hz at 15-sec intervals irritate burrowing rodents & motivate them to move to a more comfortable home P3 International Molechaser for your yard or garden Chases away rodents unharmed by emitting a penetrating sound; doesn't affect pets Easy to bury flush with the ground for easy mowing; covers up to 9,000-square-feet Includes convenient battery change cylinder 1-3/4-inches in diameter and 15-inches long at 6.6-ounces; backed by lifetime limited warranty This product is a sonic product, the sound will not be heard by humans.