Charge up to 2 small USB (universal serial bus) compatible electronic devices off your 12V (volt) or 20V MAX batteries when AC (alternating current) power is not available. Allows for work with all DeWalt Slide Style battery packs. Indicates when unit is powered on and ready to charge devices. Similar to a fuel gauge, indicates the amount of power remaining in the battery. Durable enough to withstand jobsite abuse.