If you only use your cordless tool occasionally, you should probably NOT purchase this charger. This charger will NOT charge a completely dead battery. According to Milwaukee Tools tech service, the battery must have ~3V of remaining charge in order for this charger to charge the battery. IF THE BATTERY VOLTAGE IS BELOW ~3V, THIS CHARGER WILL NOT CHARGE THE BATTERY.This is probably not an issue for somebody who uses their tools often, but if you are an occasional user (less than once per month), it is a real pain. If you have 18V batteries, buy theMilwaukee 48-59-2818 18-Volt to 28-Volt Lithium-Ion and NiCad Slide Style 1-Hour Battery Charger. It's cheaper and it WILL charge completely dead batteries.