A women-specific fit and the super-breathable mesh back panel come together to make the Osprey Women's Sirrus 36 Backpack the comfortable choice for long, demanding day hikes or quick overnights. The AirSpeed suspension system blends the rigidity of aluminum stays with a tensioned mesh back panel for effective load transfer and cross ventilation, while the Women-specific Spacer Mesh hip-belt and shoulder straps ensure your load rests where it should for maximum efficiency and pain-free hiking. An ErgoPull waistbelt closure makes cinching down the belt a breeze, and its hip-belt pockets hold your smartphone, sunnies, or quick snacks to keep your spirits high. Then, ensuring you don't sacrifice a good night's sleep, the wide-mouth access sleeping bag compartment with divider compresses and stores bulky loads, while the sleeping pad straps give you extra external attachment options. And if rain starts to fall on your adventure, deploy the integrated rain cover to keep your gear dry as a bone. A Stow-on-the-Go attachment features let you stash your trekking poles or ice axe for hands-free walking, and the compression straps help you adjust the pack's volume to fit different load sizes.