Guest On-Board Battery Charger - 15A - 3-Bank This Guest On-Board Battery Charger - 15A - 3-Bank features individual sensing and control for every bank with easy-to-read graphics that indicate the status of each battery bank through the charging process. It is 100 waterproof and shock resistant for all fresh and saltwater applications. With in-line fuses for maximum DC wire protection and new digital charging technology, this on-board battery charger is built for long lasting use and extreme dur