Please note: The BCDC1212S Battery Charger is designed for installation within the vehicles cabin or in a similarly protected environment such as in a truck canopy, caravan or battery box. Keep your trailer’s battery fully charged while on the move eliminating the need for unnecessary idling and reducing the dependence on shore power charging. Designed with REDARCs tried and tested charging technology, the BCDC Trailer S features a DC-DC charger, an MPPT solar regulator and a smart battery isolator all packed into one compact, lightweight unit. The BCDC Trailer S has an input current limit specifically designed to allow you to connect directly through your trailer’s 7‐way plug and existing vehicle wiring for easy installation. Combines a 12A tow vehicle charger and a 40A solar regulator into one unit for simplified power management. 40A solar regulator enhances off-grid adventures, enabling longer and more reliable power supply. 12A tow vehicle to trailer charger ensures batteries are charged and ready by the time you reach your destination. Built-in isolator prevents accidental discharge of the tow vehicle’s battery, ensuring safety and reliability. Protects tow vehicle wiring and fuses by efficiently managing current draw Suitable for applications where the input current required to charge the trailer battery is drawn through the vehicle's towing harnesses and connectors. The ideal battery charger for enclosed trailers - such as travel trailers, horse trailers, mobile service vehicles & emergency vehicles.