Osprey make a lot of packs: these are from their 'Superlite Ventilated' range. Sadly, we have to report that all the other models were just too heavy to be included in this survey. But these Exos packs are quite radical in their harness design. I will quote Osprey here first: "AirSpeedSuspension, which teams a 6061-T6 Aluminum frame with a 3D tensioned mesh backpanel and side crescent ventilation. The AirSpeed suspension works in tandem with the supportive and ventilated Bio-Stretch harness and hipbelt..."
What does this mean? Imagine a rim of white aluminium tubing (Easton tent pole type) twisted into a very fat inverted T shape, like distorting a large bicycle tyre. The vertical part of the T goes to the top of the harness, while the cross-bar at the bottom forms part of the hip-belt wings. Add a couple of thin reinforcing wires across the middle. Now stretch tough non-stretch nylon mesh over that frame. That's what Osprey have done: you can see the taut mesh in the middle photos, with bits of the white tubing at the edges.
But what about the lumbar pad? Well, there isn't one. Nothing there at all in fact. Very strange. The whole thing rides on the tension in the mesh across your back. Does it work? Indeed, it does, and the Exos design is quite popular. I suspect it might prove a little cool or even drafty in the snow, but in summer time it sure provides lots of ventilation.
The Exos range is another user of narrow webbing and matching buckles. The range also has some rather innovative shoulder straps. They seem to be nothing more than strips of perforated foam covered in a light mesh. Actually, I think most of the strength of the shoulder straps (and the hip belt) comes from the innocent-looking binding running down the edges. Anyhow, the shoulder straps work fine.
While the pack weights are fairly close to the mark, we have to point out that the measured volumes are significantly less than the claimed volumes. This is a pity.
Osprey Exos 46 Pack
|Exos 46||Recommended||A bit small, but very light|
We let this pack sneak in when it was only 46 L, below our threshold of 50 L, but the measured volume is way below the claimed volume. Ah well. Doubtless for a fully-fledged UL walker in summer this might be adequate volume even so. However, I found it made an excellent pack for a serious day walk, shown in the right hand photo. It had plenty of room for all our gear, leaving my wife with nothing to carry. That was a novel experience for her! The pack rode quite well.
Osprey Exos 46, 1.05 kg (2.32 lb), 40 L (2400 cuin), S, M, L.
The back of the pack has fairly common open pocket on it, made of stretch fabric and held up by a buckle. That much is obvious. What is less obvious is that there is a vertical pocket behind the open one, with a vertical zip. You can just see the pull on the slider next to the buckle on the lid in the left hand photo. That is all very well, but try getting something into this pocket when the main bag is full. It is rather unlikely. Perhaps you could slip a small poncho in there, but it had better be dry as there are no drain holes.
The lid pocket has a key clip inside it and there is a zipped mesh security pocket under the lid. I suggest that anything you store in the mesh pocket should be in a waterproof bag. The lid pocket itself has reasonable capacity for a lid pocket.
Osprey Exos 58 Pack
|Exos 58||Recommended||Fair volume, carries well|
Having already described the Exos 46, there is little new left to say about the Exos 58. It is bigger of course, and it has two concealed back pockets with vertical zips rather than the one on the Exos 46. Curiously, while the left and right pockets are separate, there is a mouse hole between them right at the bottom. Very odd. You can't get much in either one when the main bag is full. The novel shoulder straps were described above. It was noticeable that they were quite comfortable. The hip belt was quite comfortable too. There are zipped mesh pockets on the hip belt, but I found them of little use myself.
Osprey Exos 58, 1.19 kg (2.61 lb), 50 L (3000 cuin)
The lack of a lumbar pad did not worry me, but Sue was able to feel the aluminium frame tube running across the bottom of the harness on this Exos 58 pack, but less so on the Exos 46. Somewhat curiously, this bottom tube was well curved on the Exos 46 but less so on the Exos 58. Why this is so I do not know. On the other hand, the slightly greater curvature on the Exos 46 meant that the tube in the wings was closer to the sides of Sue's hips, and was slightly intrusive there - but not badly. Perhaps one could fine-tune the curvature in the tubular frame, but I am not sure how much of that the high-tensile aluminium tubing would take. Perhaps this is a design more suited to men than to women?
The photo on the right shows the Exos 58 in the Australia Alps, on a nine-day trip in autumn. No, I did not get food for the full nine days in there: we had a posted food drop half-way along. Cheating of course. With only half the food, the pack was still pretty full, but we were carrying some winter gear in all that. You can just see a trace of blue under the lid: that was my tent, sitting on top of the throat and under the lid. The single strap under the lid held it in place well enough. Why am I squinting like that? Because there was a howling gale blowing across the plains at the time!
I got most of the gear inside the main bag for this trip. I think I had my poncho in one of the zipped back pockets - that's all. Our blue foam sit-mats went in the open back pocket, the same as you can see in the right hand photo of the Exos 46 above. That worked fine. Over all the pack rode well on this trip, and I was quite happy with it.
This is a mini-review in the 2010 Lightweight Internal Frame Pack State of the Market Report. The articles in this series are as follows (mini-reviews can be found in Part 2), and a subscription to our site is needed to read them.