Roll it where you need it. The DeWalt DXAEC200 Battery Charger and Battery Maintainer is the high efficiency automatic solution for cars, trucks, SUVs, marine vehicles and RVs. It provides a powerful 200 amp engine start, 40 amps of charging and 3 amp maintainer. Compatible with standard 12 volt AGM batteries. Built-in circuit protection guards against overcharging, reverse polarity or short circuit. The alternator check tests the vehicle's alternator to indicate if it is operating properly. Electric pulse technology can help reverse sulfate build up on battery plates to improve charge capacity and extend battery life.