Fully automatic 3-stage charging (bulk, absorption and maintenance)Low line voltage compensation delivers true-rated output even when input voltage dropsRain tight, shock and vibration-resistant constructionShort circuit and reverse polarity protectedFor use with 12V/6-cell batteries (50-130amp hour rating) that are flooded/wet cell, maintenance-free or starved electrolyte onlyFCC compliantUL listed to marine standard 1236