This 12 Amp Fast Charger has the highest charge rate in our 20V MAX and DEWALT FLEXVOLT; Lithium Ion battery range, minimizing downtime on the site. The new Stage 1 and Stage 2 LED indicators communicate more about the battery state of charge than those without. The Stage 1 LED blinks until the battery is approximately 80% charged. It then stays solid and the Stage 2 LED blinks until the battery is fully charged.