Psst! You can do better than Harbor Freight panels. There's used panels out there that offer as much as 300 watts of 12 volt power, and they're CHEAP, compared to new price for high-end panels.And now this battery is treated kindly all the time by being on a set of two Harbor Freight solar panels (of 4 from their kit) when my trailer is not in use.
And all four panels together are very helpful on even a cloudy day to keep this battery topped off when camping with no commercial power.
Rick
Just sayin'.....Roger