Nice one Bob. I have one of the older Sears ones. You know the kind. They are a metal box with vents. Mine is a 2/10/30(start). It works pretty good, but with several cars that I don't use in the Winter, it is a pain, so I also bought a battery pack, but I still have dead batterys. Now I am using battery maintaners. I bought them from Harbor Freight for about $8 each. Now they are only $4.99.
They are nice and small, light, and work. I just unplug it from the wall or extension cord when I want to move a car. The car starts right up, and I just put the plug under the hood. When I put the car back, I just plug it back in. But, even with these, every garage still needs a good charger.