CamelBak M.U.L.E. Hydration Pack 12LPacks that go the distance. We shifted our gears to update your go to pack so you're never left trailing behind. You get the same trustworthy M. U. L. E. with slight body modifications for a smooth ride and fit. Both Men's and Women's feature smart storage options, Air Support Back Panel, lightweight materials, and max ventilation to keep you feeling and looking cool on the trail.