When I bought my Makita 18 volt kit, this light was included with all the other tools. Before using it, I thought it was the dumbest thing ever. I've come to learn that it's one of the smarted, best designed cordless work lights ever. I have no idea how long it will stay on with a single battery because I've had it on for over 6 hours when we lost power, and it was still working. I put it in an attic when I'm on a job and just leave it on until I'm done. I had it under my backhoe the other day for a few hours while I removed a couple of hydraulic hoses. That flashlight was the only good thing about that day!!!