The Yellow Jacket Low Impedance Fencer operates on four D batteries or a 6- or 12-Volt external battery (not included). Will  power up to 10 miles of wire fence and will control all types of animals. UL-listed YJ1 features a weather-resistant, nonconductive cabinet that shrugs off rain and snow and features built-in wire clip for mounting and built-in ground rod mounting clamp for easy installation, portability and versatility. UL listed.