Shoulder the Backcountry Access Stash ALP 55 Backpack and set out on a multiday alpine climb or overnight backcountry skiing trip. BCA's Stash hydration system runs the drinking hose through an insulated shoulder strap and down into the pack where it connects to a Nalgene bottle (not included). Outlast insulation inside the shoulder strap stores your body heat and releases it to warm the water when you're not movingyour water won't freeze on a long belay, or when you stop to dig a snow pit. A plastic frame sheet with aluminum stays comfortably supports the load while you're climbing up. BCA even gave the Stash Alp 55 Backpack a side zipper so you can see if your water is running low or pull out your belay jacket without unclipping the top pocket.