Lots of minor issues. But I'm pretty sure it's garbage. First, I have the wrong system voltage. It's off at 0.2V. I thought maybe my onboard system voltmeter was off so I connected a multimeter to the battery terminals and to the charge controller battery terminals and they both read +0.2V higher, or just that, what my embedded system is saying. Also, even in full midday sun with a 100w panel it tells me I'm plugging in 2 amps. Third, I'm pretty sure it's actually draining power since my batteries are FALLING faster than usual. I do not recommend this product. Spend 40β¬ for something better.