£139 / €169 / $179

The AX40 is the same size as the AX35, but with a floating, removable lid (instead of a fixed one) for greater versatility in packing different load volumes.

For its size and weight, the AX40 is extremely well specified, having every necessary feature that is expected of an alpine sack, yet at coming in at only just over a kilo, sacrifices nothing of overall robustness and durability. It is seriously tough. The harness borrowed from the AK sacks has a decade’s worth of refinement; balancing comfort and support with a minimalist profile. This carrying system is probably the best you'll ever find on a climbing sack anywhere in the world.

The AX40 is available in a single, unisex back length.




External lid pocket
Security pocket on inside of lid
Floating removable lid
Side compression straps – quick and easy to fit or remove
Oversized back haul loop – easy to grab and clip
Top compression strap
Dual drawcord closure system on extension sleeve
3 mm Tendon drawcord – can be used as emergency rap anchors
40 mm webbing waistbelt with low-profile full-sized hip-fins
Internal sleeve for hydration bladder
Two ice-axe holders
Wand pockets
Reinforced, double-layer base panel

Technical Specifications

Capacity 40 litres
Weight 1050 g
Fabric 15% Dyneema / 85 % Cordura, 150 g/m², ripstop
Frame Two 9.00 mm x 1.5 mm flat titanium stays (removable)

One size only

Knowledge Base

For more information about our backpacks, please click on the following links below.
Sizing and fitting of crux backpacks
The physics of backpack design
Using the features of an AK pack