This is a technical piece of electronics. You must read the directions. If you know the truth about charging your batteries with a solar panel then this is the only controller to get. I can easily adjust the voltage going to the batteries to insure it will not cook the batteries and still get them fully charged. The auto equalization mode is fun to watch on my trimetric monitor.PS You must install Diodes and fuse the power lines.

I like it. Thanks.

I wanted to learn about solar/wind energy and this appeared to be the most flexible controller I could find for the price.This charge controller is fairly unique for the price. It allows a large range for voltage input VDC 0-150 (or 140v - I don't remember) to charge a 12v battery. There are also 24v, 36v, 48v versions. It can be used with Wind, solar, other DC alternators. It is a hackable / expandable controller.This unit does not include a blocking diode (this prevents the power from the battery flowing back to your input source).I ended up buying mine form an Ebay "buy it now" vendor as it was noticeably cheaper.I put a link to the manual in the comments. If you are not willing to read the manual multiple times, I would not recommend you buy this charge controller. An exception may be if you have some assist in you setting it up. Make sure you have a volt meter to monitor your battery voltage. I know when I did my 1st real test it appears it is over charging my battery. Now I need to go back and figure out why. (Good learning experience)Parts in the manual are an interesting read even if you don't end up buying the controller.I will update my review at some point.