Light weight, large bladder and practical packaging make it versatile
The Unzen 6 from Shimano uses a unique strap design dubbed the X-Harness to hold the pack stable against your back.
Rather than two conventional straps with one or two bracing straps as on the Ergon and most other designs, the X-Harness has shaped straps that come together on the middle (like an X) and hook together for added security. An additional narrow waist strap stops any unwanted fore/aft motion. The harness is hugely adjustable so getting it to fit just-so is easy.
Access to the two-litre bladder is via the back panel – which opens completely for easy access – and the routing of the hose is neat, although, like the Ergon, the lockable bite valve is stiff in use.
The main compartment opens nice and wide and has several different pockets for separating out your tools, pump and sandwiches, while a separate padded and waterproof pocket holds your phone and valuables, although I found this a very tight fit with my regular sized iPhone so big phone users beware!
Other useful features include straps to carry a full-face helmet and a stowaway rain cover in its’ own pocket.
In use the pack felt secure and very comfortable. Padded panels on the rear allowed a little airflow but in the heat of summer sweaty backs were still the order of the day. The main compartment is big enough to carry the essentials for a long ride with space for a small jacket if needed.