The Coleman 30 Amp Digital Charge Controller is the ideal solution for preventing overcharging of your 12-Volt batteries and protecting solar panels. It contains a digital display that provides either the charging current or the battery voltage on the LCD digital meter. A charge controller is an essential part of nearly all power systems that charge batteries. Its purpose is to keep your batteries properly fed and safe for the long-term. The basic functions of this controller are to block reverse current and protect against battery overcharge battery discharge electrical overload and/or display battery status and the flow of power. Protects battery from overcharge and discharge For use with 12-Volt solar panels and batteries only Handles up to 30 Amp of array current Handles up to 450-Watt of solar power Maintenance free protection of your solar panel and batteries Maintains 12V batteries in a fully charged state Continuously displays the charging current or battery voltage on the LCD digital meter Automatically indicates the charged condition of your battery on the LED status indicators Safety features include: safety circuit protection discharge protection thermal protection and easy wire protection