Prior to this unit had a traditional dumb car charger for a long time, but it died this year.Replaced it with a Black & Decker unit - you may see recommendations for it in your search. That unit refused to charge any battery given. Returned for refund.Bought this Ampeak unit hoping for more luck and after a day or so of reconditioning walk into the garage to see it 50% charging on my completely dead AGM battery that only held 3 volts, .2 amps before.So far I’m pretty happy. Clear screen, clear indication of what it’s doing including a display of the current voltage. If it brings this long neglected battery back from the dead I think it will work with anything else I have for it.