Coxa’s R5 pack uses a four-way strapping system that’s said to give increased freedom of movement for your shoulders.
Getting the pack on/off is a bit tricky, requiring the waist and shoulder straps to be clipped/unclipped at the central closure, and the shoulder straps to be Velcroed/detached from each other.
If you’re one for regularly accessing your kit, this will cause some frustration. But if you’re not, the pack stays in place fairly well (unless it’s overfilled) and remains comfortable and not too sweaty.
Getting the fit of the straps just right is vital though, and takes a bit of figuring out – although this should only need doing once.
The 5.5-litre of storage comes in the form of a main compartment with a single mesh organiser inside, although there are mesh stash pockets on the waist strap and rear of the pack (which also has an integrated light) too, which can be accessed without taking it off.
Packing the bag would be easier if it had more structure to it, because it tends to fold in on itself while you’re stuffing kit in. At least the provided bladder is held in place well with Velcro loops.
Water flow through the valve is fair and the reservoir is easy to open. The theory behind the pack makes sense, but on the trail it just falls short in performance terms.