Here's a word to the wise on using a trickle charge with an AGM (Absorbant Glass Mat) battery. Late model Challengers come with an AGM battery. AGM batteries cannot be maintained with conventional battery chargers. You must use a charger/maintainer that is specifically designed for AGM batteries. If you connect a conventional battery charger to an AGM battery, the charging indicator will light but never turn off. It will simply keep charging the battery until it is overcharged and, if left on too long, will damage or shorten the life of the battery. AGM batteries require chargers with microprocessors that regulate the charge rate and have the correct logic to turn off when the battery is fully charged.