HART 2-Pack 20V 4.0Ah Lithium-Ion Battery for Power Tools - Compatible with 20-Volt Cordless Drills, Saws & More (Charger Not Included) - Perfect for DIY Projects, Home Repairs & Construction Work

Dislikes: noneLikes: charge fast using the Hatt 20V4Ah charger.(these will charge on the Hart 20V2Ah charger, but take a lot longer to reach full charge).Also like they have 4 bkue L.E.D. bulbs that indicate how much battery powet is left in the battery, all 4 lit = 4 hours, 3 lit = 3 hours, 2 lit = 2 hours, 1 lit = 1 hour or less.At least from my use of these batteries, this seems to be very consistent. When Charging as the battery reaches its full charge these 4 bulbs will turn on to show what power level the battery is currently at, when it reaches its full charge, all these bulbs are turned off and charging stops.There is a small square, blue button next to the bulbs, just press it in and it will show you exactly how much power is left in the battery, a very useful feature, my original 20V2Ah battery doesn't have this feature, I wish it did!I charged my batteries when I received them to full charge, that's been around 2+ months, they have been sitting on a shelf since this charge, pressed the button to verify charge status, all 4 bulbs lit up bright blue, so they hold a charge for quite some time while being stored for future use.Excellent batteries, work well, last longer, and holds charges longer, highly recommend these for your 20V battery powered Hart Tools.