- The lightest backpack for multi-day hikes that includes a built-in frame is the Zpacks Arc Blast Backpack. The 45 Liter pack size weighs a featherweight 20.8 ounces. The base cost is $315, with larger sizes and additional pouches and pockets costing extra.
- The lightest backpack without a built-in frame is the the Mount Laurel Designs Exodus. The 40 Liter Exodus weighs 17oz and costs $195.
- Standard multi-day packs typically weigh between 60 and 84 ounces.
Ultralight backpacks are ideal for hikers who enjoy taking a minimalist approach to backpacking, as they allow you to cover more ground than do traditional packs. Read about the basics of Ultralight backpacking here. The Arc Blast has an ultralight Flexed Arc carbon fiber frame that transfers most of the weight away from the shoulders and to the hips. It also creates airflow between you and your pack. Custom made, the Arc Blast can carry up to 35lbs of gear- good for at least a three-day outing.
In addition to a main compartment, the Zpacks Arc Blast comes standard with removable hip pockets, a water bottle sling, and a tent pole pocket. The outside of the pack is adorned with loops you can attach gear to, as well as a fully removable lid for the top of the main compartment. Members of the ultralight backpacking community have commented that the updated version of the Zpack Arc Blast, released in 2015, has new hip belt fasteners, the ability to raise and lower the pack height, and a new padded hip belt which goes all the way around the torso.
The Arc Blast has a Cubin Fiber interior as well as a protective layer of 50 denier Polyester on the outside to minimize rips and tears, but as with all ultralight packs, durability is still a concern and the pack is inadequate for winter or rainy season.
Other Alternatives: Ultralight Multi-Day Backpacks
The Osprey Packs Exos 48 Backpack offers an excellent compromise between durability and weight. At just over two pounds, the Exos 48 sports an ExoForm sewn-in hipbelt with mesh-covered foam for external comfort. It is an ideal starter pack for those interested in minimalist hiking.
The Osprey Packs Exos 48 is available at Amazon for around $190.
Other ultralight weight packs, such as the Mount Laurel Designs Exodus, are even lighter (the Exodus weighs 17oz), but they lack the built-in frame and therefore require padding for extended hiking expeditions. The Exodus costs $195.