When day hikes stretch out into more committing endeavors, the Osprey Sirrus 36 women's hiking pack is the perfect in-mid-size option. Its top-loading design, topped by a fixed top lid, helps make packing a breeze. Plus, with its highly ventilated AirSpeed® suspensions system and just enough volume to empower your bigger pursuits, it inspires long days and lightweight nights exploring our more rugged trails, rain or shine. Made with 100% recycled materials. Key Attributes AIRSPEED® VENTILATION Injection-molded suspension system w/ 3D-tensioned mesh provides breathable support. Osprey Sirrus 36 Litre Women's Overnight Hiking / Daypack with Raincover