Always power ready the tool and the second battery are ready to use upon arrival at the jobsitemaximum productivity automatic charging function while you driverobust robust design and charging without contacts via the l boxxcharging while driving made easy the ready to go l boxx bay comes complete with an inverter enabling it to be easily connected to an available 12v cigarette lighter in the vehicle then you can start charging on the way to your next jobfor 12v connections