BLACK+DECKER BM3B 6V and 12V Automatic Battery Charger/Maintainer Charges and maintains 12 volt and 6 volt AGM, GEL and WET batteries Easy connection to vehicle battery using battery clips, O-ring terminals, and DC accessory plug Stops charging automatically when battery is fully charged or topped off, switching to float mode monitoring Built-in circuit protection guards against overcharging, reverse polarity, or short circuit; ETL certified for performance and safety Mounting bracket built-in to charger for convenient placement