OYMSAE 20W 12V Solar Panel Car Battery Charger Portable Waterproof Power Trickle Battery Charger & Maintainer for Car Boat Automotive RV with Cigarette Lighter Plug & Alligator Clip

Put this on my starter boat battery so it stays topped off between use. Battery is always at full charge when I use this, so I have permanently put a plug in wire on battery. I plug in, put cover on boat and strap this maintainer onto the top of cover as wire is long enough. When I use boat, I take the cover off and unplug the maintainer as part of the, "ready for water" process. So far, so good. There is a hole in all 4 corners so bungies works great for tie down of maintainer to cover straps. Don't know if will charge a battery but not my purpose.

This solar panel is easy to hook up with multiple different connection options. The supplied wire is not long enough for my particular application but that is easily fixed. I currently have it hooked up to a charge port instead of a direct battery connection. Once I get the wires extended it will be hooked up directly to the battery via the supplied connection adapter. It should be long enough for most vehicles.It keeps the battery from getting discharged on my vehicle. It is currently installed on my Expedition which usually stays in the driveway and only used for hauling. The battery kept getting drained down due to not driving the vehicle on a regular basis. This is far more practical than burning fuel just to keep the battery charged.The install was very simple with the supplied suction cups. I do intend to mount it more securely to the dash in the near future.The size lends itself well to a windshield mounted application and does not cause a visibility problem.I highly recommend this for anyone who has a modern vehicle that sits for long periods of time.

I had the 10W model but upgraded to this 20W because my car doesn’t get that much direct sun this time of year due to the sun’s angle. The increase wattage definitely made a difference, even on a cloudy days. Can’t wait to see how it performs later in the year when the days are longer with the sun directly overhead.

I have just connected it to a 16AH battery and itHas peaked up tie voltage to 13.8 volts which is correct for a fully charged battery. I have not measured its output warts but it seems to be doing the job.

Often have to leave the car over a month in a parking lot, I just keep this in the sunniest window (just lightly wedged) and it keeps the batteries topped off the entire time! Also got one for the old farm truck, both vehicles diesel with 2 batteries and they're right at 12.6v at night. Mainly use the 12v ciggy plug.

It’s fast and easy to use and set up with d rings and suction cup mount and has different hooks up and very light weight.

I installed this to keep my battery charged in a car I don't drive as much as the other and it starts right up every time I do drive it! It works well!

I didn’t use suction cups to mount it. I have it mounted in my dump trailer to help keep battery topped off while not being used. Has been working great to keep battery tended and recommend getting for smaller setups would get bigger one if it would of fit where I had space for it to go.