Berghaus Bioflex 45 (2012)

Prepare yourself for a totally different sensation when walking with this backpack, as Berghaus unleashes its BioFlex technology on the world. This unique back system sees the hipbelt pivot with you as you move, allowing you to bend forward and flex without being encumbered by your load. It does feel odd at first and takes some getting used to – it won’t be for everyone – but you can ‘lock’ the system so it doesn’t move if you like.

The Berghaus Bioflex 45 sits quite close to your back with ridges to help aid airflow and reduce sweat. But they do dig in by the shoulder blade, as does the top part of the hipbelt – so this is by no means the comfiest pack here. The pack is divided into two compartments. They can be joined together by a zip, but the problem is that when zipped up it doesn’t fit flush to the walls of the sack, so small items can fall from the top to the bottom compartment easily. The raincover also takes up a fair amount of space in the bottom compartment too (but can be removed). The lid, wand and hipbelt pocket are a good size but I found it more of a squeeze to fit all the same items in as I did with other sacks on test – especially as the lid was not floating. The Berghaus Bioflex 45’s compression straps could have benefited from all having quick-release clasps, though the fact the top two did was a bonus.

Weight 1.50kg

Capacity 45 litres

Compartments 2

External pockets 1

Wand pockets yes

Hydration pocket yes

Back lengths 2

Floating lid no

Men’s option yes




The Berghaus Bioflex 45 is a revolutionary way at looking at a back system – though it may be a bit too heavy, slightly small and pricy for those who aren’t convinced by its benefits.

Review by Phoebe Smith

First published in Trail magazine Spring 2012