This is a good basic charger for small batteries. It was perfect for my bike, a charger that turns off when the battery is full and really good at not turning on at the slightest sign of a voltage drop which is what you need for battery maintenance. It's fully automatic, detects 6 and 12 volts, has only three indicators (bad polarity, charging, fully charged) and can turn off if you connect the wires in the opposite direction. I also used this device to charge a large car battery. I doubt it could bring the big battery back to life after it was completely drained and it took forever (1-1/2 days) to charge the big battery from max to full but in the end it got the job did. as long as it's known as a trickle charger/trickle it's very, very good, especially for the cheap price. By the way, the length of the device is 9-10 inches, which is much longer than the photo suggests. The item in the picture looks almost like one of those mini chargers that plug into a cigarette lighter, but is more substantial.
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