It is on sale at Costco, but I bet it will be available in other places as well.
I've been using "solar water heaters" who in 1 gallon size were great addition to RV when used without hook ups.
Filled up with lake water, or some campgrounds had water spigots not only extend the stay, but are also convenience when you spend the evening at campfire.
This tank brings the idea to whole new dimension.
Big, but still easy to carry and can be pressurized with hand pump, so no over head hanging.
Click on video that shows multiple uses.
DAY TANK