Sierra Designs HD3 45-60L Rucksack

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Tough, adaptable, and ready for serious terrain, the Pajak HD3 45–60L is built to meet the demands of technical expeditions and alpine missions.

Pajak says: 

This backpack is your ultimate companion for outdoor expeditions and climbing adventures. Designed with durability and comfort in mind, it offers ample storage, exceptional support, and climbing-specific features, making it perfect for both short hikes, long treks, and challenging climbs. Ergonomic support ensures maximum comfort during extended use, while the high capacity allows for adjustable volume to accommodate gear for various lengths of expeditions. Constructed from durable materials like X-Pac® Carbon Fiber, it is built to withstand the toughest conditions. Equipped with climbing-ready features, including gear loops and reinforced straps, this backpack ensures reliability and performance in the most challenging environments.

Our Verdict

The HD3 45–60L impressed me with its blend of rugged materials and practical features. Weighing around 1,070g, it manages to feel remarkably sturdy without being overly cumbersome. The X-Pac fabric reinforced with carbon fibre and Dyneema lends real confidence when scrambling or hauling over rough ground. The adjustable volume, ranging from 45 to 60 litres, is a thoughtful touch, allowing me to streamline the pack when carrying less or expand it for longer trips.

Access to the kit is straightforward thanks to the roll-top closure and an additional back panel entry, which I found particularly beneficial when I needed to grab gear quickly. The ergonomic back support system and stable harness made heavier loads feel manageable. 

The integrated RECCO reflector adds a welcome layer of safety for remote mountain days, and the gear loops and daisy chains are well placed for lashing on axes or crampons.

– Reviewed by Ultralight Outdoor Gear

Features

• Ergonomic Support
• High Capacity
• Durable Materials
• Roll Top Closure
• Gear Loops

Specifications

• Weighs: 1070g 
• Volume: 45-60 L
• Dimensions: 65(85) x 30 x 20cm

Material & Construction

• Fabric: X-PAC® CARBON FIBER
• Components: YKK™ WOOJIN, X-Pac Dyneema

Help and advice:

• The Ultimate Guide to Choosing an Ultralight Rucksack
• Time-Saver Guide to Choosing a Rucksack