This is what I use. Works great, actually bought it for the sole purpose of tuning my truck but now have used it for conditioning friend's batteries and charging
www.harborfreight.com
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2/10/40/200A 6/12V Automatic Battery Charger with Engine Jump Start
Amazing deals on this 2/10/40/200A 6/12V Auto Battery Charger at Harbor Freight. Quality tools & low prices.
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