Volpi Outdoor Gear UL40 ultralight backpack - is the lightest thru-hiking pack on the market. The backpack feels very light but is pretty roomy with a volume of around 45L. 

This frameless pack weighs 430 grams together with the hipbelt (is removable). Unlike a lot of ultralight frameless packs this pack has load lifters to pull the pack closer to your back. Even though it is frameless, if you fill it up with enough stuff you can definitely carry the load on your waist and the load lifters pull it in towards your shoulders. 

Roll top closure provides excellent top compression, it can compress down to about 28L, so it looks tiny the last day of the resupply.

The outside mesh pocket fits quite a bit of stuff and you can also use attachment points on the shoulder straps and hip belt.

It's made with Challenge Ultra 100/200 a highly abrasion resistant, ultralight and waterproof fabric made by Challenge Sailcloth. Ultra fabric is likely the lightest, strongest, most durable and waterproof fabric on the market today.

With its textile technology and minimalist design, the UL40 can be used as a daypack but is even a perfect choice for long-distance trails.

MATERIAL

Challenge Ultra 100 - Wolf Grey
Challenge Ultra 200 - Black, White

Challenge Ultra is a laminate fabric that combines a UHMWPE woven face with a laminated film backing to produce a fabric that has:

• Extremely high tear and tensile strength
• Maximal cut, abrasion, and wear resistance
• Super high and long term waterproofing

FEATURES

• Water Resistant
• Frameless
• Removable Padded Hipbelt
• Not seam sealed

MEASUREMENTS

Torso: 43 cm | 17 inches

Height: 50 -70 cm | 20 - 27.5 inches

Wide: 27 cm | 10.5 inches