Review on Upgraded SUNER POWER 12 Volt Waterproof Solar Battery Charger & Maintainer Pro - Advanced MPPT Charge Controller - 18W Trickle Charging Kit with Built-in Solar Panel for Cars, Boats, Motorcycles, RVs, and More by Michael Hughes

After reading the reviews of the 20 watt solar charger I came to the conclusion that it was worth it. Of course, some people may have gotten one that leaks, but that's obviously not the norm - mine is NOT currently leaking. Looks well assembled, I chose not to remove the battery cover to measure the current - too much hassle. The light flashes red to indicate charging and I know that behind the tinted glass the efficiency is well below potential. With the camper in storage I was afraid someone might be tempted to grab it, so I bought more watts than I wanted so it could work indoors, just plugged into a 12 volt outlet. I have charged the Group 27 batteries of a fantastic Honda 2200i and will be testing the camper in a few days. To charge internally I had to unplug the battery disconnect plug and pull the LPG detector fuse as it draws about 0.28 amps. This left a tiny red LED on the switchboard to indicate an error and I assume it draws little to no power. I will update when I know more. UPDATE: I have found that tinted glass and glass in general degrades the performance of solar panels VERY. Overcame laziness and measured the amps, bouncing between 0.00 and 0.09, sometimes stopping at 0.06. It's a foggy day here, but outside and flat on the ground I'm reading 0.67 amps. No doubt full sun and the right angle will do much more. I have a new seat at the top of the stairs and an extension cord. See second picture. Update 2021. I still love this product and wish they would make a 50w panel in the same mould.