*6 V @ 750mA *3-step fully automatic charging (qualification, bulk charge, float) *Charges/maintains sealed, maintenance-free, AGM or flooded lead acid batteries. *Spark proof even when output leads touch. *Reverse Polarity Protection- no charger damage / no battery damage *State of charge indicator- 2 -color LED *12 foot output cords *5 -Year Warranty. "A battery tender is a battery charger that is designed to maintain the charge in your battery when the car isstored for an extended period of time. However, it will charge a "dead", but still usable battery if it is used for an extended period of time (12-36 hours)."