The SV10 & SV5 energizers are ready to go straight out of the box: A reliable built-in rechargeable battery and integrated solar panel make the JVA Solar Energizers totally portable, without the need for extra batteries and hardware. The energizers have an LCD display enabling you to see the voltage and joules on the fence at a glance. Just slide the energizer onto any Y-standard, connect the fence and switch it on. The SV10 Energizer has 1.0J output energy and the SV5 Energizer has 0.5J output energy per pulse. They are suitable for permanent and temporary fencing.