I was using a 'waterproof' pouch bag to store my keys and documents while swimming. Well, it was waterproof until because of wear (after a few uses) I've got a small punctation in the edge, and everything was wet inside.
I don't want to damage my car keys, and my scuba diving friends have recommended me the scuba diving egg like this: to be full water proof in the shallow waters.
The problem: how to use it while swimming? When I'm swimming with a swimming bag, it's not an issue, but then I don't need anything else to store my keys. But swimming shorter distance near to shore, I don't need a swimming bag, and this egg looks as an interesting alternative. But I have no idea how can I mount it so it doesn't be awkward while doing swimming strokes (a wrist would be quite a terrible choice, obviously).