This highly adjustable model may be one of the heaviest in the review, but it carries large loads in comfort For aggressive trails or alpine travel that involves boulder hopping, frequent river crossings, or terrain nearing Class IV, more flexible suspension would be prudent. Thanks to room for 55 l worth of personal property, this creation is mainly aimed at adventure seekers going on more demanding journeys. This unsurprisingly makes for amoderately unwieldly article but the ergonomically shaped shoulder straps are well capable of offering more comfort. Most important of all, the dimensions are 78 cm x 38 cm x 25 cm. More & More Space

The flatter profile of the Aether’s suspension system allows for more weight and stability but presses into your body more. So the Aether can hold more weight but doesn’t offer the same feeling of lightness (or the same level of ventilation) as the Atmos. Other Notable Differences Basically, Aether’s anti-gravity mesh is much flatter, so presses against the body. Providing support for a higher load weight, also means that you’ll feel more of the weight and that the ventilation isn’t as even. Note: The hip belt might be a bit on the small side for the high end of the range, but for loads in the 45-plus-pound range, I believe the suspension would remain stable and comfortable. That said, I do prefer the Osprey Aether thanks to its higher weight capacity and removable DayLid. But, the Atmos may be better for you at least in certain situations. Front mesh, 2 hip belt, extra storage straps & loops, (Total 7 + main compartment) water bottle storage on both sidesZippered lower sleeping bag compartment with an internal, removable divider and sleeping bag straps But all that comes with one caveat: The large volume and the long feature list denies the Aether 55 and Ariel 55 ultralight status. Our L/XL Aether has a verified weight of 5 pounds 5 ounces while our XS/S Ariel is 4 pounds 13 ounces. Though both the Osprey Aether and Atmos feature an anti-gravity suspension system, they work in different ways. The latter two are what they call the Custom Fit-on-the-Fly design, this is all added for a fine-tuned fit and for a variety of body shapes & sizes. Adjustable both torso length and shoulder padding. Sleeping bag compartment (zippered) with a removable divider to afford your sleeping bag extra protection