My battery is not reliable, but might be ok. I did not want to fork over the money for a new battery at $80-100 quite yet. There are many options out there. I stumbled upon this one, available at both Sears and Kmart. I also got a deal by getting almost 40% off with an online deal and picked it up within an hour at the actual Kmart. This thing is tiny compared to other jumpers. It has no fancy decals, lines or molding. Actually, it looks nice and simple. It's heavy for it's size, which I take as a good thing. The short cables are thick and long enough, the plastic housing is heavy duty. Very nice. I charged it first (per instructions), however in minutes it showed full. Jumped me on the first try. I have a small Toyota. The 500 amp rating is low compared to others, but I've used it a few times now and it jumps me right away. Charges fast and the socket on the back will be helpful during a power outage. Time will tell, but so far, it's worth it. 1 yr warranty too.
I charged the unit as stated the light turned green to fully charged left plugged in a few more hours after that went to turn my car over and nothing not even a sound of trying to start. Got a standard jump from a small 4 cylinder car battery and started up no problem. Don't buy unless you have something very very small!