Kind of like a giant Platypus. A cruiser just back from the 'hamas with some rigging issues I consulted with last week gave me one. He said they worked great, especially when he had to haul water to the boat. When empty, pack *very* small, and the price is very low, $7 per.
https://smartbottleinc.com/product/5-3-gallon/
Yep, great concept, had a similar 5 gallon for camping. It had molded in creases so that it collapse smoothly to flat. It had a recessed spigot near the bottom, and weighed a pound or so. The carry handle was about an inch in diameter, for comfortable carry. The fill hole was about 2 inches, and had a screw on cap, so easy to fill. Great engineering.
The price was right, my brother in law picked it up off the highway median, and gave it to me. It was empty when he found it, so no impact damage when it hit the ground off the pavement.
I think I still have one of those aboard. Very handy :)
I have 6 of these on the boat.
Easier to shuttle water in the dinghy than going thru the hassle of docking.
Looks much better then the ‘Coughlin’ flexible plastic water container. I had one of those self discharge all over my settee years ago…. Hauled around 4 5 gallon hard plastic jugs after that….
Thinking on how these might be better (in some ways) than building integral tanks like I'd been planning - which would save lotsa time *and* money. Being so flexible they'd conform to small and/or odd shaped spaces. They have, among others, sizes of 1, 2.6, and 5 gallons, along with a line of accessories now like filler caps/tubes. They'd make it east to capture rain, while keeping it from possibly contaminating water already aboard.
Once emptied, they could be blown up with air to provide flotation. Extras stow in no space at all, and the price simply blows away any other solution.
They are already surprisingly tough. Even so, it'd be very easy and quick to make terrycloth or fleece waterbagbags for each one to guard against chafe - see illustration.
waterBagBag.jpg