The framebag one I've got definitely doesn't stay closed without the hard plastic bit but the Platypus one I tested might. It's more ziplock whereas the Hydrapak kinda folds over and is held shut like a roll-top bag.
Platypus big zip
@skinny started
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The framebag one I've got definitely doesn't stay closed without the hard plastic bit but the Platypus one I tested might. It's more ziplock whereas the Hydrapak kinda folds over and is held shut like a roll-top bag.