Tech Specs: Running: 15A | Engine start: 50A | Maintain: 3A
I actually own this model of charger/maintainer, and I can say with confidence that it's a great choice for all skill levels. The backlit LCD screen makes it easy to see charging status, reversed connection warnings, and charging mode selections.
The push-button controls make it quick and easy to check battery voltage, test the alternator, jump start your car, or charge the battery. With the 15A quick charge mode, it took just over three hours to bring my old Chevy Cobalt's battery back to full after being drained by an interior light.
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The unit also automatically switches from quick to trickle charging when the battery reaches full capacity to avoid overcharging that can cause damage.