The Porter Cable PCC580B 18V Battery Status Indicator gives you a fully automatic status of charge indication for 18V Lithium-Ion or NiCd batteries. It has illuminated LEDs that show charge status - 1st LED on -low charge, 1st and 2nd LED on - partial charge, all 3 LEDs on - 75-Percent+ charged. If no LEDs are visible the battery has a very low state of charge or no charge at all. It has an automatic shut off after 15 seconds that reduces battery drain. Remove battery after use.