ReviewSpecsGalleryRetailersRabs expansion and development of its backpack range continues apace, now with larger packs that might once have been the sole preserve of sister brand Lowe Alpine joining their range, as well as the smaller, fast-and-light style packs that featured in their initial launch range.The differentiation between Rab and Lowe Alpine? Well Rab packs are certainly more techie, using the latest hi-tech fabrics to give the best weight/strength performance, as well as innovative back systems and other features, with Lowe Alpine tending to give a more traditional offering.This pack we have on test, the Hyperon 65L, is described by Rab as our definitive pack for exploring far-flung regions where self-sufficiency is key, this 65L backpack is geared up for serious multi-day adventures, from long distance trekking to shorter expedition use. It certainly looks the part, with its blue/black colour scheme (grey/black also available), chunky hipbelt and mesh-clad back system and straps. Its clean design belies the fact that it packs in a lot of features, both in terms of adjustability and storage options but well come to this shortly. Lets start off with a look at the packs all-important carry system.The Hyperon 65s back length is easy to adjustCarry systemThe Hyperon comes in two sizes M/L and L/XL and in addition to this the back length can be adjusted using a hook-and-loop system. Unlike some other hook-and-loop designs where its a struggle to keep two surfaces apart (and not sticking together) while adjusting the length, the Hyperon has a more refined design which is simple to adjust; just pull the outward facing side of the back panel away and then slide up or down on the two metal stays to get the ideal back length. The entire carry system including a very pronounced lumbar pad makes use of thick perforated foam which is intended to maximise ventilation at the same time as assuring comfort. The hipbelt arrangement is interesting in that it has slots behind he lumbar pad and moves independently with its own, curved metal stay giving it structure, and is also heavily padded with a large, zipped pocket on each hip.StorageAs we said earlier in the review, the Hyperon 65 has a clean and unfussy profile, and that is exactly how we like our packs here at T&M, but when it comes to storage it is absolutely rammed with options. The packs main compartment features a (removable) fabric divider near the bottom, which allows you to access a sleeping bag or other item directly via its own zipper. Not only that, but the upper part of the main compartment also has its own zip, so again, you can access items in this area without having to open the main lid. Speaking of the lid, theres no less than three internal and external zipped pockets located here, all good sizes each, with a security key clip inside the internal pocket. On the front of the pack theres another pocket with a vertical zip that could be useful for keeping a spare layer, or other items you want to access quickly, and naturally you also get a mesh drinks pocket on either side at the hips. Were not finished yet! Theres a zipped pocket on either side of the hipbelt itself, and finally, theres smallish zipped pockets at the sides, towards the top of the pack, which will fit objects such as a 1L water bottle.Out testing the Hyperon 65 in Langdale Valley in CumbriaIn useThe Hyperon 65 weights in at a not inconsiderable nor unreasonable 2.6kg, but like all well-designed trekking packs it feels almost weightless when you actually put it on. The fabrics used feel really tough and durable, and you just get the feeling that this pack is not going to let you down. The pack has both internal and external compressions straps; having them inside the main compartment means you can position items where you want them and ensure the pack is stable even when moving on rough terrain. On the outside, the lower straps thread through the side mesh pockets, and if like us, you like to carry tent poles at the side in these pockets, then youll appreciate being able to cinch them in tightly. But what matters most, of course, is the ability to carry a load over a long distance with the minimum of fuss and discomfort, and in this respect the Hyperon 65 delivers big time.VerdictLoads of storage options, a comfy carry and tough as nails make this a super trekking packMore info at: www.rab.equipmentSPECSWeight: 2.6kgMain fabric: 210D ROBIC Nylon with Spectra Ripstop and Hydroshield Dura coatingBack lengths: 48-58cm (M); 53-63cm (L)Secondary fabric: 210D ROBIC Nylon Ripstop with Tri-Shield CoatingVolume: 65lt/3965cu.inDimensions: 82 x 37 x 46cmBack system: V-TRAXFull specs and features at: www.rab.equipmentBuy the Rab Hyperon 65 online at:Ultralight Outdoor Gear