Charger automatically switches to Float Mode when fully charged Absolutely no danger of overheating or overcharging Leave it connected for months at a time if necessary Designed to charge AGM, sealed maintenance free, lead calcium and flooded batteries Manufacturer recommends checking battery fluid monthly 4-step charging (Initialization, bulk charge, absorption mode, float/maintenance) Spark Proof Temperature compensated Short circuit and reverse polarity protected 10-year manufacturers warranty These chargers do NOT meet California/Oregon appliance efficiency standards