Chase away those stubborn garden pest, moles, gophers and voles. Get rid of the the railroad tracks that are running through your yard.  This set of 2 environmentally friendly solar powered pest control sound device emits a powerful ultrasonic wave through your lawn to eliminate ground hogs and other varmints. No poison, no chemicals, will not harm the family pets or your farm animals. Effective coverage about 7000 square feet. Emits sounds underground every 30-50 seconds. No wires to plug it. It's solar powered panel makes it ideal for do-it-yourself homeowners. For best results, it is recommended to use 2 units approximately 60 ft. apart in the highest risk area.