Solar Panel Charge Controllers protect your 12 Volt Batteries from being overcharged by solar panels.  If you use solar panels over 8 watts and leave it charging your battery for long periods a Solar Controller for Small Solar Panels is essential to protect your battery.  Simply install the Solar Charge Controller in between your battery and the solar panel and when your battery is full it disconnects the charge. We sell the Sunforce and Sunlinq  Solar Charge Controllers including the Sunforce 7 Amp Solar Charge Controller, Sunforce 10 Amp Solar Charge Controller, and Sunlinq 7 Amp Solar Charge Controller.