Review on 🌞 SUNAPEX 10W 12V Portable Solar Battery Charger & Maintainer - Intelligent Charge Controller - Solar Panel-Built - Solar Powered Charger for Car, RV, and More by Rudy Hilmy

This is a 10W panel which of course will never deliver 10W. That is the nature of these things. In direct, bright sun, however, I was able to get about 7.25 watts. 13.2V at 0.55A. This was connected to two 12V 100Ah batteries connected in parallel, which had around 85% SOC. It's fine and met my expectations. It needs to be in direct sunlight at a nearly perfect angle from the sun to generate that much power. Other panels I've had weren't as picky. They could also generate their 70 percent at a less than perfect angle and not at the highest intensity from the sun. For the price and my use ok. I just need the trailer backup battery and that should do the trick. If you have large batteries and need more than just a trickle charge, these panels aren't powerful enough. This conversation starts at 100 watts. The reason for the -1 star is because the advertising says they are weatherproof. The seller has responded to questions that they are weather resistant. However, the panel is clearly marked as weatherproof on the back. In particular, it cannot be used in the rain. But maybe. But that is impossible. It's an illusion. I'll go ahead and spread it out, and if the rain ruins it, well, the rain ruins it. I look at these things from an economic point of view. It only takes me three months to amortize instead of paying a $15 monthly fee to top up in storage. If you don't have that economic benefit for your use and/or you really need something more weather resistant, you can throw away this device.