Battery Tender Battery Tender Plus - 12V 021-0128The Battery Tender Plus is a 1. 25 amp battery charger designed to fully charge a battery and maintain it at proper storage voltage without the damaging effects caused by trickle chargers. Included is a quick connect ring terminal harness for hard to reach areas and alligator clips for an alternate connection. Temperature compensated to ensure optimum charge voltage according to ambient temperature. Automatically switches from full charge to float