Solar battery tender

I have a vehicle that sits sometimes for an extended amount of time. I would like to keep a charger on it without running an extension cord. Can any recommend a good solar powered charger?

I used one from Harbor Freight on my enclosed trailer winch battery, kept it charged all the time since it sat outside.

https://www.harborfreight.com/15-watt-solar-battery-charger-62449.html

I use a solar-powered unit made by Battery Tender to maintain the batteries on our trailer. About $100 on Amazon for the large unit I have. Works great.

- EM

If you buy the Harbor Freight one when it's on sale it is pretty painless. It does seem to work, assuming you have a car that the cigarette lighter is always hot. I have one but the truck it was going to serve has a cigarette lighter that turns off with the ignition.

R.