Sweeney's 9012 Mole and Gopher Twin Pack Sonic Spikes (not available in HI, NM, PR) Moles and gophers are chased away unharmed Spike covers up to 7,500 sq. ft. Sonic pulses emitted every 30 seconds Operates in a circular pattern, approximately 95 ft. in diameter Requires 3 "D" batteries (not included)