MC4 connectors are generally considered waterproof. Panels are generally considered waterproof.
The amazon link shows that item no longer available. It appears to be two 50w panels with a hinge. Understand that 100W isn't much output - more like trickle charging. You
might get 5A on a good day.
I have a pair of 80 watters for 160 total, works fine. Just not a lot of juice. A portable is also something you can make if you're handy - rivet a pair of hinges on any pair of solar panels and a couple of pivoting standup legs. The good news is being portable they can be placed where there IS sun at a campsite, and pointed directly at the sun. I use mine to augment main battery charging, and to charge a small solar generator.
These portable units used to be very reasonably priced, but got stupid expensive over the years. I think I gave about $150 for mine, about eight years ago. If you have room for rigid panels, they're surely less costly that some of these fancy flexible foldable arrays offered these days. Most of them come with some kind of solar controller, but a SCC should really be as close to your battery as possible. I have 25' 10gauge leads from panels to SCC.