Featuring the latest state-of-the-art solar panel with superior charging power the Parmak Magnum 12 Solar-Pak eliminates battery recharging, thereby saving you time and money. The sun's energy charges the fencer by day and a sealed, 12V rechargeable battery (included) powers the fencer at night. When the unit is first turned to "ON" position, the performance meter on front of fence charger now performs 3 exclusive functions: 1. meter operation test 2. battery charge level test and 3. fence charger voltage output on fence. Weatherproof, portable outdoor model. Charges up to 30 miles of fence. UL listed.