Versatility, a womens specific fit, and surprisingly large capacity for its weight only 4 lbs. 9 oz. in medium, the Osprey Womens Ariel 75 backpack is an excellent choice for climbers and backpackers who enjoy multi-day trips but want to keep the weight to a minimum. The recommended capacity of the Osprey Ariel 75 womens backpack is in the neighborhood of 40 lbs. so the suspension and harness need to be solid. Coined the AirScape suspension, it consists of peripheral 7075 AL rods, an internal HDPE framesheet with single aluminum stay and a covering of ventilated nubbed foam and mesh grip. This covering, or backpanel, provides superb contact yet still allows air to circulate. Connecting to the suspension, a womens IsoForm custom moldable hipbelt and IsoForm shoulder harness with dual density foam and Spacer Mesh surface evenly distributes the load. Most women find that the harness and hipbelt that comes with the pack is the correct size for them, but other sizes are available for an exact fit. Regarding the custom molded hipbelt, contact Osprey customer service at 970-564-5900 for molding instruction upon delivery of your pack. An overall key feature of the Osprey Ariel 75 backpack is its versatility. For those monster loads into base camp a stretch woven front pocket offers extra carrying capacity when the main compartment is stuffed. And then for go-light day trips from camp, the top pocket mates with the hipbelt to make a terrific lumbar pack. The Osprey Ariel 75 womens backpack is also Osprey Excessory compatible, meaning a choice of add-ons can be installed to further boost the backpacks versatility and capacity.