Review on KONNWEI KW510 12V 5-Amp Smart Charger with Car Battery Tester - 3 in 1 Automotive Pulse Repair Maintainer, Trickle Charger Battery Desulfator with Temperature Compensation by Aaron Carney

****UPDATE*** This charger has already saved me about $45. My lawnmower tractor battery was completely dead and after checking/testing it was recommended to be replaced due to a bad cell. Then I kept myself that I bought Konnwei that was in the trunk of my car. To my surprise, this little device fixed the failed battery and charged the battery in less than 5 hours. It has already paid off! and the tractor starts immediately. THANKS AGAIN. Needed an AGM charger/maintainer as my old charger only works with regular acid batteries. I'm glad I found the KW 510 - it's a tester too. I have tested various car batteries and their charging systems. One battery needed charging, which wasn't a problem for this device. Double checked and while the voltage is there the inrush currents are significantly lower (367 out of 800). I left the charger plugged in for makeup/charging/maintenance, to my surprise I can start it with no problem even though the CAs are less than half a new working battery. The repair function didn't solve the problem, well the battery is 5 years old but rarely used which most likely killed it. When I get a new one I leave it plugged in to be carefully serviced/refilled at very low amps. Time will tell how the device performs, but for the moment I'm satisfied and can recommend it.