We bought these for an international trip where we had to swim long distances and didn't want to leave valuables in a bag. They have worked brilliantly for this purpose. Can't comment on how well they worked underwater etc because we didn't do that much. Ours swam. We bought four and there were three of us with phones. One of them broke during our 2 week trip but for the price I think they've held up pretty well. If you want something durable, all you have to do is find and pay for higher quality. But with a backup, they worked fine for our rather adventurous trip. And I would buy again.
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