The BAUER™ Lithium-Ion, 4 Amp Battery Charger works 2X faster than standard chargers,* minimizing downtime on the job. Built with full system compatibility, this fast charger is capable of charging all BAUER™ 20V batteries. This charger was designed with a built-in microprocessor that monitors the health of the battery to prevent overcharging, overheating, or charging when there is damage to the battery cell.