Hello each other
This bag can be used well for and with as a buoyancy aid. It is waterproof with 3 wraps and have tried it myself and top satisfied.
I used it for a standup paddle trip and fell into the water a few times *laughs*. Everything stayed dry :).
Greetings
Daniel

In my opinion, this bag is not comparable to a wrap-around fish. It is made of much harder material and not for swimming in the sense of a buoyancy aid, but rather for transporting swimming gear. I am not sure if it is really waterproof...