The Deuter Gravity Series Expedition 45 L pack is an ultra-light pack ideal for longer alpine adventures and multi-day climbs when you need to bring bivy gear on route. This pack combines functionality and weight savings, and has lot of helpful features for stowing gear including a built in gear loop on the waist belt and loops on the back for securing ice tools. The pack itself weighs just over a pound, and is extremely comfortable to hike and climb in. As a fairly tall woman with a smaller build I often have trouble finding packs that not only fit well but are comfy to climb in as well. The Gravity Series Expedition pack does it all. I have used it for hauling gear to the base of routes, as well as bringing along on bigger alpine climbs when I need the extra room for gear. It has been an asset on long alpine climbs and I look forward to testing it out on a multi-day climb on Mount Stuart next month.