Parker Mccrory Mfg Company DF-SP-LI-UO REPLACEMENT 6 volt - Solar/Battery Operated Electric Fencer Replacement unit ONLY for DF-SP-LI & DF-SP-SS Will fit inside all DF-SP-LI and DF-SP-SS battery cases; Must be used as a replacement unit - No weather strip provided Simply remove unit mounting screws, remove old unit, disconnect wires, and replace with new unit Battery wire connectors included ; Charges up to 25 miles of fence UL Listed