Smarter than a trickle charger, our 4 Ampere will fully recharge and maintain your battery. Get a quicker charge on automotive, marine, and powersport batteries with this everyday charger which is compatible with 6 Volt and 12 Volt AGM, flooded and gel batteries. For safety, it's spark-proof during lead connection and automatically detects reverse polarity to ensure a correct, locked-in connection before providing power.