When you’re on walkabout in a damp climate, you’ll appreciate Osprey’s Ultralight Raincover. The stuff sack lets you pack it tightly until needed. Then, this piece of coated nylon will help you avoid spending a night shivering in a soggy sleeping bag. Fits 75 -110 liter packs.
The XL cover is not big enough for an Aether 70 with a Thermarest Z-Lite SOL (accordion style) sleeping pad mounted horizontally to the back. I tried mounting it vertically, and could barely get one of the pack's back straps around the pad even though the pack is far from stuffed and has only 30 pounds in it. The cover barely got around the pack. Pretty frustrating, especially since the Aether Owners Manual shows the pack with this style sleeping pad attached to it.