The PWRCORE 20™ 4.0Ah lithium battery powers all tools in the SKIL 20V lineup so you can take on anything. Green LEDs show the battery’s charge status in 25 percent increments so you’ll know how much charge remains. It’s lightweight and compact at just 1.62 lbs, so it won’t weigh down your tool. You can use this lithium battery to power up anything in the SKIL 20V lineup from power tools to outdoor power equipment.