AK27

【Store Manager's Comments】

The British brand [CRUX]. Its defining features are, without a doubt, being "completely waterproof" and "highly durable!" Just hearing that alone gives you a sense of total peace of mind. While you might worry that those two traits imply significant weight, it’s actually incredibly lightweight—so much so that you’d never guess it by looking at the specs. (Every customer who has held one has been surprised, haha.)

It doesn’t have any convenient external features like side pockets, but that’s exactly what makes it so appealing—you can customize it and attach gear exactly how you want. This is truly the best backpack for activities where your gear is bound to get wet, such as canyoning, backcountry skiing, and packrafting!

The AK27 features a top-lid design; while it is a 20L pack, it has an actual capacity of around 30L. It’s the perfect size for day trips like canyoning or hiking.

Unlike the roll-top RK series, this model includes side pockets, making it easier to secure items like trekking poles, paddles, or skis. (Note: These pockets are not designed to hold bottles.)

According to the representative from the import agency, there has never been a repair they couldn't handle, which is another major plus since you can use it for years to come.

【Manufacturer Quotation】

A lightweight, completely waterproof alpine backpack that has continued to evolve since the inception of CRUX.

A model born as a Japan-exclusive launch, incorporating functionality designed for use in Japan.

Packed with features not found in packs over 30L, it is completely waterproof and built to withstand harsh weather—snow, rain, and more. It is built for rugged use in climbing, canyoning, mountaineering, ice climbing, sailing, and kayaking.

AK Series [Top-Lid Type]

The top-lid style offers a higher storage capacity compared to roll-tops, provides the ability to secure ropes or mats between the lid and the pack, and offers excellent waterproof protection in rainy conditions.

【Four Pillars of Peace of Mind】

① Completely Waterproof

Uses welding technology. The seams are bonded rather than stitched to prevent water ingress. Furthermore, the lining features a coating with a water resistance rating of 10,000mm, achieving waterproof performance comparable to professional rain gear.

Because it is completely waterproof, you can feel at ease during rainy hikes, canyoning, and alpine climbing. The roll-top section uses flexible material to enhance airtightness, ensuring a complete seal. You won't need a separate dry bag, which also helps lighten your load.

② High Durability
Uses Kevlar. Due to the durable nature of the material, you can feel secure knowing it won't easily tear on rock faces, walls, canyons, or ice routes.
It is a material designed to withstand strong contact with or pressure from trail structures like rocks, ice, and branches, as well as gear like ice axes or ski edges.

③ Simplicity

By keeping the design structure simple, the pack is protected as much as possible from trouble, such as breakage, even during long multi-day trips or expeditions.

④ Repair

Spare parts are available for most components, allowing for easy replacements. Furthermore, we have established a system where repairs are carried out at the factory of origin whenever possible, ensuring that you can cherish and use your backpack for a long time.

【Features】

 - Aluminum buckles are used for high-frequency points (top lid, waist belt) to reduce the risk of breakage.
- Ice axe holder
- Side compression straps
- Thick mesh material for improved sweat and water drainage
- Detachable waist belt
- Haul loop
- Upper compression strap
- Top lid fixation

【Specs】

- Capacity: 20 L (Feels more like around 30L)

- Weight: 975 g

- Size: One Size

- Material: 40% Kevlar, 60% Nylon

- Frame: None

- Country of Origin: China

【Manufacturer Description】

A British brand established in 2002, focusing on climbing, alpine climbing, and mountaineering.

Started with just 4 types of backpacks and 1 type of tent.

Today, the category has expanded to include sleeping bags and bivvy sacks. The lineup is carefully curated, developed with a focus on items that are truly practical for the mountains.

Products are developed based on real-world climbing experience. From the Himalayas to Patagonia and across Europe, and through a wide range of climbing styles—from alpine to sport—we reflect the necessary specifications in our products and continue to develop gear for climbers.