By "2.5 - 5 liter" do you mean the bladder capacity or the volume of the pack in general?

I've had an Osprey Raptor 10 for about 8 years now. It works well as a mountain-bike pack and a light day-hike pack. I also use it for winter runs when I want to add or shed layers of warmth. It rides close to the body without a lot of bounce, so I like it for that. It came with a 3 liter reservoir for hydration, which I always assumed was part of the 10 liter total (?). My wife has a larger version of the same pack.

I have soaked the thing in sweat and dust many times and rinsed it clean. It has held up well under my abuse.

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