Product Code: CX-RK-40-3G



The RK40 is simply a bigger version of the RK30. The only other difference aside from the volume of the sack itself is that the RK40 has sleeves on the inside that allow frame-stays to be inserted. This makes the pack more comfortable if one is lugging heavy loads around (and a big rack with a couple of ropes would qualify as such).

Accessory pocket at rear
Dyneema® cord compression system
Oversized back haul loop – easy to grab and clip
Top compression strap
Two ice-axe holders
Option to fit two stays to stiffen back carrying system
Welded construction throughout - fully waterproof

Technical Specifications

Colour Black, Red
Capacity 2440 cu. in. / 40 litres
Weight 2 lb 10 oz / 995 g
Fabric 40% Kevlar / 60 % Cordura, 7 oz/yd² / 240 g/m²
Frame Option for two 0.275in / 7.00 mm Ø tubular titanium frame-stays (not supplied with product)

R (regular)
L (Long)

Delivery & Returns

All our products are shipped with FedEx for quick, reliable and secure delivery. As most of our products are quite large and/or of high value, they will require a signature. We cannot deliver to P.O. boxes. All orders are dispatched the next working day after receipt (Monday to Friday). Typical delivery times are 2-3 days.

If you are not satisfied with your purchase, you can return it for an exchange or refund provided it is within 90 days of receipt of your order and the item is in the original packaging.

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