This Solar Battery Charger with Solar Charge Controller is the next generation maintainer / charger for all your 12 Volts lead-acid batteries. Connect the solar panel with charge controller to your battery, when not in use. It automatically charges, maintains your battery without electricity and without fear of overcharging your battery. It is simple and reliable. Its energy-saving performance will save your money on battery purchases by extending the life of your batteries. Built-in blocking diode protects against battery discharge at night. Rugged design works in all weather conditions, is maintenance-free, includes pre-cut holes and mounting screws for easy installation.