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Apart form Alpkit Gourdon - anything? Or is it best just to use dry bags inside? Don't want a cover btw
Bump
Whilst not officially waterproof, my kit has never got wet inside my osprey raptor. I do wash it with Nikwax TX direct wash-in though.
Ortlieb Flight or Ortlieb Mountain. No personal experience with them but they seem solid.
Aldi do a good one.
Best one out there is your existing pack and this:
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Short of that, Macpac still do a small running/cycling pack out of Aztec fabric that is semi-waterproof (not a dunk underwater).
Wingnut hyper! Job done perfectly waterproof and an awesome pack to boot!
Having checked out the price of the Ortliebs I think the Gourdon gets my vote....
just ordered a gourdon as a commuting/days when it is pissing down bag.
looks great for the price
Exped have a few waterproof bags, they look rather similar to the Gourdon (and more expensive).
Or something from Over Board. http://www.over-board.co.uk/backpacks/waterproof-backpacks.html
Though not sure if they can take a hydration pack