Light without sacrificing fit and comfort, the Osprey Aether 85 Backpack is newly updated for backpacking and mountaineering pursuits. You will love the custom moldable hipbelt and the clean aesthetic appeal of this pack. The 2/3 length aluminum stays provide lightweight yet strong Strength. The Aether 85 can carry between 5000-540 cubic inches depending on the size you choose. (S,M,L) The top pocket can be removed and converted into a lumbar pack using the IsoForm hipbelt on the pack. The Aether 85 features a reservoir compatible dual exit system for you hydration necessitys. (The reservoir is sold separately)