What's It For?
The Exos 46 is Osprey's new lightweight backpacking sac. Unlike other lightweight packs however, Osprey has incorporated a lightweight frame to cope with heavier loads and hasn't skimped on features. A lot of lightweight packs constrain what you can carry and can make for a truy miserable day if you overload them. The idea behind the Exos is to be able to have your cake and eat it. And carry it around with you too, if that's your thing.
The Techy Bits
Osprey has gone to very obvious lengths to save weight on the Exos. The fabrics themselves are very lightweight generally but heavier in obvious wear points. Then there are the fixtures and fittings - the z-type side compression straps use what Osprey calls 'Tiny Tape' and are, in effect, miniaturised. Buckles and fasteners generally are the lightest on the market to save those vital extra grammes and pockets use mesh.
So how on earth has Osprey cut weight this low and still incorporated a frame? The key is the minimalist back system which uses a 6061-T6 aluminium perimeter frame with obvious similarities to the Atmos, backed up with two fibreglass cross struts. On top of that the back-system is suspended, so the contact point is a mesh trampolene. The air gap's been kept to a minimum though in order to stop the pack levering away from the back when loaded up. Straps and hip-belt use die-cut EVA which also has built-in stretch to improve fit and allow movement.
The end result is a pack that has an impressive grammes per litre ratio compared to its competitors. The Exos 58 weighs in at 17 grammes per litre of capacity, compared to 30 gramms per litre for the own Atmos 50. To put that in perspective, the minimalist GoLite Jam 2, which we also have on test, scores around 12 grammes per litre, but has no frame and rather fewer features.
How It Performed
We've always been impressed with Osprey's attention to detail and build quality, so we were expecting a lot from the Exos. First impressions were that it's an incredibly light pack considering the number of pockets and features. The side stuff pockets and big back stretch pocket were ideal for stowing shell clothing, gloves, water bottle and so on and we also appreciated having a proper lid pocket on long days out.
The cavernous side-entry zip-pocket was great for, say, stowing an insulated jacket or fleece for stops and we did really appreciate it.
Another neat feature is Osprey's 'Stow and Go' pole holder which hangs the poles from your shoulder strap with the lowers anchored to the side of the pack. It keeps them well out of your way and allows you to pole and de-pole without taking the pack off.
All the features, in fact, that we'd expect from a much heavier back-packing sac. And they worked just fine.
The question you're asking though, is how does it carry with a decent load. And the answer is impressively well. Osprey packs like the Atmos have always done a clever trick where no matter how heavy a pack feels when you pick it up, it seems to halve in weight as soon as you put it on your back.
The Exos manages this trick too, despite aggressively minimalist shoulder straps - they'll be wider on production models, but we found them comfortable enough anyway - and hip-belt. With around 12 kilos or so, which is a reasonable lightpacking load, it really did feel extremely comfortable, stable and thanks to the narrow air gap, had no leverage issues either.
The hip-belt - as some of our OM guinea pigs noted - does sit slightly high when the pack's lightly loaded, but fill it up and it assumes a more natural position and carries well. As an experiment, we chucked a measured 18.4 kilos in the pack, more than we'd expect to carry normally, and it was still emminently useable, which is nice to know, even if you don't plan to carry that sort of weight regularly.
Some of our testers found the small buckles, say on the compression straps, slightly fiddly when used with gloves and we'd agree with that, there was also one issue with the hip-belt buckle unclipping occasionally, but we found it fine in use.
What else? We've ripped a hole in a Talon before now, but the Exos has survived unscathed so far, Tiny Tape and all. We like the shock-corded ice axe / pole top fastener and the hip-pockets are as useful as ever for compact cameras, snacks, lip-salve and whatever else you need easy access to. We suspect the vented back will be pleasant in warm weather, but we've had none of that recently...
Verdict
A lightweight pack that still carries heavier loads with comfort and stability? You'd better believe it. Not only that, but Osprey has managed to cram loads of useful pockets and features, like the Stow and Go pole carrying system onto the pack without making it heavy.
The combination of alloy frame and suspended back system really does seem to suck the weight out of any load you put in the Exos and even with over 18 kilos, it was still useable if not luxurious. With loads of 12 kilos or so, it's simply just very comfortable and very stable.
Design and build quality both seem to be excellent and the features on the pack simply work and work well.
Buy if... you're looking for a top quality, lightweight pack with all the features you're every likely to need, that doesn't require you to go ultra-minimalist on your kit.
