The 7.5Ah ARC Lithium Battery is now equipped with an upgraded fuel gauge. The new built in indicator lights lets you see how much run time you have left. With 5 segments wrapping the power button, you can now see how much battery power you have left in 20% increments. The ARC Lithium battery technology is the industry's most advanced; equipped with patented Keep Cool Cell Technology; which keeps the cells cool and prolongs the life of the battery. | EGO Power+ 7.5 AMP Battery