6 volt battery operated. Americas first solar-powered electric fencer is now equipped with the latest state-of-the-art solar panel. Increased output, longer life. Solar-Pak eliminates the need of expensive battery replacement or inconvenient recharging. Built-in performance meter shows exact condition of the fence line. Solar-Pak will operate for 21 days in total darkness. Weatherproof, outdoor model. Charges up to 25 miles of fence. Complete with sealed 6-volt Gel battery. UL listed, Low Impedance. Made in USA.