The SealLine 55-liter in use holds quite a bit, but not too large to carry. Anything that you really want to keep dry (say toilet paper, paper towels, flour, sugar . . . ) needs to be in a dry bag. Trash bags, used by a lot of cruisers, don’t do nearly as good a job: they get a hole or two almost immediately and then any water in the bottom of the dinghy gets into the bag—and big splashes also seem to make their way into the trash bags.