Thunderbird Battery Tender & Charger – A must-have accessory for T-Bird owners who store their cars for the Winter or other long periods, uur Battery Tender is the most popular brand among owners of the 2002-2005 Thunderbird. Unlike other types of chargers that can cause damage, our 1.25 amp unit is designed to fully charge a battery and maintain it at proper storage voltage and automatically switches from full charge to float charging mode. This unit is temperature compensated to ensure optimum charge voltage according to ambient temperature and will charge as fast or faster than any 3-amp charger. Reverse polarity protection ensures user safety and uses flashing red and green lights alternately. Includes a quick connect harness for hard-to-reach areas.