The all-new Ariel Backpacks boast Osprey's best-fitting design for trekking technical terrain comfortably, and the Ariel 65 is the biggest backpack in the bunch. Sized for weeklong trips and weekenders, the Ariel 65 is a solid choice whether you're carrying heavier loads or just enough gear for a night. The back torso adjusts vertically to customize the fit for all sizes, and On-the-Fly shoulder strap and waist belt adjustments ensure quick-and-easy micro-adjustments that you can cinch on the trail. Osprey not only integrated a rain cover, but also treated the main fabric in DWR in case you don't get the cover on in time. A LightWire frame offers surprisingly stiff rigidity for how light the pack weighs, and Airscape mesh provides breathable ventilation on your back.