Osprey has a strong reputation for building comfortable packs, and the Aether line is one of their best. Updated last year, the Aether AG adds Osprey’s signature “Anti-Gravity” suspension to mix. To see how it performed, we loaded down the 70-liter model for a multi-day trip in Utah. Despite the overhaul, the core ingredients remain: a strong suspension, excellent comfort, and thoughtful organization. It’s definitely not a lightweight pack at over 5 pounds, but should be a top choice for comfort seekers and those who need a heavy hauler. Below we break down the Aether AG’s carrying comfort, ventilation, organization, durability, fit and sizing, and more. To see how it stacks up, see our article on the best backpacking packs.


Carrying Comfort

What made the prior Aether pack so popular was its ability to comfortably carry a heavy load, and the updated Aether AG 70 continues the tradition. We took the pack into Utah’s Canyon Country to an area with limited water availability, which meant we were hauling a number of reservoirs and bottles on our trip. The Aether handled the 50-pound load with surprising ease—we found the high quality foam in the hipbelt and shoulder straps hit that just-right combination of comfort and support. Backpackers that keep weight down likely won’t need this luxurious of a pack, but we certainly appreciated the extra cushion on this occasion.
Osprey Aether AG (logo)

In addition to the excellent foam padding, the Aether AG has a strong metal frame and suspended mesh back panel that create a great feel. The peripheral metal frame and center cross support provide a solid structure that doesn’t sag under a load. And the suspended mesh back panel—Osprey calls this their “Anti-Gravity” system—molds really nicely to your back. More, the numerous compression straps along the sides and front of the pack keep your gear in place. Even among luxurious packs like the Gregory Baltoro, the Aether AG is extremely comfortable.
Osprey Aether AG (backpacking)


Osprey’s Atmos AG, which we tested a couple years ago, is the best internal-frame pack we’ve used in terms of ventilation. The suspended mesh back panel and hipbelt encourage quite a bit of airflow. For this 2017 update, the Aether shares the “AG” or “Anti-Gravity” suspension with the Atmos. This means the open mesh back panel sits a couple inches away from the pack itself to keep air moving and you comfortable.
Osprey Aether AG (vented panel)

In use, we’ve concluded that Osprey traded some of the amazing ventilation of the Atmos AG for the greater comfort of the Aether AG (a fine compromise for many people). As such, we did end up with sweaty backs in the 85°F heat of Utah, which was the most noticeable along the non-ventilated hipbelt. In very similar conditions with the Atmos, we had far fewer issues. That being said, the sections of mesh along the lower back did outperform many other bags we’ve tested, including Gregory’s Baltoro.
Osprey Aether AG (ventilation side view)


The Osprey Aether AG has the organization you would expect from a feature-rich pack. The top lid has 1 medium-sized and 1 large zippered pocket, and the main portion of the bag has a large mesh pocket along the front. In comparison, we do prefer the more secure zippered front pockets that flank the mesh shove-it pocket on the Gregory Baltoro, but the Osprey's stretchy pocket is still a handy feature. To round out the organization, a J-shaped zipper is great for accessing items in the main compartment, and the 2 hipbelt pockets are plenty big for smartphones and had no issues holding a point-and-shoot camera (our Sony RX100). Those carrying trekking poles or an ice axe have plenty of attachment points.
Osprey Aether AG (zippered access)

Water storage on the Aether AG is just as good: the two water bottle pockets have top and side access, which make it easy for grabbing a bottle without taking off your pack. And the stretchy material can hold a Nalgene even when the interior of the pack is full (this is a problem we’ve run into with some other packs lately). On the interior, the Aether has the standard hanging loop, sleeve, and exit port for a hydration reservoir.
Osprey Aether AG (lookout)

Integrated DayLid Daypack

Far and away, one of our favorite features on the new Aether AG is its integrated daypack. Stored in the top lid when not in use, this is one of the best built-in designs we’ve seen (far exceeding the hydration sleeve pack from Gregory, for example). The daypack is easy to access: just unclip the 4 buckles holding the top lid in place, unzip the top pocket, and pull everything out.
Osprey Aether AG (removing daypack)

We were initially skeptical about the DayLid’s capacity, but it turned out to be just about perfect for our side excursions from camp. Impressively, we were able to fit our full-frame Sony a7R II camera case inside, and the comfort was quite good with light padding on the shoulder straps. Most removable daypacks, such as what you get with the REI Co-op Traverse 70 or Gregory Baltoro, are overly simplistic, but the Osprey includes a small exterior zippered pocket and a hang loop and separate sleeve for a hydration reservoir. In truth, if Osprey were to just sell the DayLid as a daypack, we would give it high marks on its own.
Osprey Aether AG (daypack)

The only downsides in the design are that stowing it cuts a little into the potential capacity of the top lid and the extra materials add some ounces to the total weight of the pack. And we’d love if the daypack had a hipbelt, but overall it’s a top-notch design for adventuring or peak bagging during the day.
Osprey Aether daypack


The empty weight of the Aether AG is the biggest downside of the pack. At over 5 pounds in all sizes in the 70-liter model (our medium weighs 5 pounds 3 ounces), this is not a pack for minimalists or ounce counters. But among high-capacity and heavy hauling models, the weight is somewhat more reasonable. Gregory’s Baltoro 75 (4 pounds 15.4 ounce) and Arc’teryx’s Bora AR 63 (5 pounds even) are two of the Aether’s closest competitors and near matches in weight. You can save about 10 ounces with Osprey’s own Atmos AG 65, but you do compromise a little in carrying comfort.
Osprey Aether AG (top)

For cutting weight, you can leave the top lid at home—the Aether has a separate flap that can be secured over the main compartment. This sacrifices convenience and storage as the top lid is a great place for keeping small items you want close at hand, but it is a way to trim some weight while retaining the Aether’s impressive carrying abilities.
Osprey Aether AG (hiking downhill)


Unlike similar trips we’ve taken with lightweight packs, we gave little thought to treating the Aether AG roughly. The durable nylon along the sides and top of the pack had no issues while scrambling up and around rocks, and the super tough 500-denier nylon packcloth on the bottom is built to last. The one area to keep an eye on is the mesh pocket along the front, but even that is pretty well protected by sections of 210-denier nylon and compression straps. Granted, we haven’t had enough time with this Aether to be totally confident, but we see very few potential problems for long-term durability.
Osprey Aether AG (bottom panel)

Fit and Sizing

Finding a pack with that perfect feel often requires trying on a bunch of models back-to-back, but we continue to be impressed with how well Osprey bags fit. Our medium size pack was a good match for our 2 testers (one with an 18-inch torso and the other at 21 inches). And we found the Velcro adjustments for the shoulder straps made it very easy to swap packs midway through the trip. Osprey does offer heat molding with the hipbelt, which gives you a close fit right out of the box, but you can accomplish the same customized feel by just wearing the pack for a couple of days.
Osprey Aether AG (waist adjustment)

What We Like

  • Very comfortable and durable for carrying heavy loads over rough terrain.
  • The daypack that’s integrated into the top lid has a fantastic design and a surprising amount of comfort.
  • Great organization: tons of pockets and it has a large zippered access to the main compartment.
  • Easy to adjust the fit/sizing.

What We Don’t

  • At over 5 pounds, it’s a heavy pack and more than some backpackers need.
  • Ventilation on the back panel is decent but not a standout.

Osprey Aether AG (big wall hike)

Comparison Table

Pack Price Weight Fabric Capacities Access Pockets
Osprey Aether AG 70 $310 5 lb. 3.4 oz. Nylon (210D & 500D) 60, 70, 85L Top, front 7 exterior
Gregory Baltoro 75 $330 4 lb. 15.4 oz. Nylon (210D) 65, 75, 85L Top, front 10 exterior
Osprey Atmos AG 65 $270 4 lb. 9 oz. Nylon (100D x 630D) 50, 65L Top 8 exterior
REI Co-op Traverse 70 $249 4 lb. 14 oz. Nylon (200D & 420D) 35, 70L Top, front 11 exterior
Arc'teryx Bora AR 63 $549 5 lb. 0 oz. Nylon (420D & 630D) 50, 63L Top, side 6 exterior

The Competition

The push for ever-lighter gear still leaves plenty of room luxurious packs, and the Osprey Aether AG fits the bill quite nicely. Its closest competitor in both price and intended use is the Gregory Baltoro. Both packs are heavy hauling specialists with excellent padding, organization, and durability. Some backpackers prefer the pivoting hipbelt on the Baltoro, although both are very comfortable. Further, we like the Gregory’s large zippered front pockets and it does come with an integrated rain cover (for more information, see our Baltoro 75 review). But the Osprey DayLid daypack easily outperforms Gregory’s hydration sleeve pack and you get better ventilation. Both are great options, and the final decision should come down to which of the pack’s respective strengths are more important to you.
Osprey Aether AG (hiking uphill)

For 2017, Arc’teryx released an update to a legendary pack: the Bora AR. The largest capacity in this bag currently is 63 liters, so it can’t match the Aether in what it can carry, but the Arc’teryx sets itself apart in both technology and price. First, the bag has waterproof panels along the top, which provide excellent protection in bad weather, but the real innovation is in the hipbelt. The new RotoGlide design rotates as you hike and even slides up and down on a track to adjust as you lean forward while climbing. At $549, it’s out of reach for many backpackers, but the hipbelt design is something the Aether AG can’t touch (along with just about every other pack on the market).
Osprey Aether AG (hiking)

Osprey makes some of the best comfort-oriented backpacking packs, so inevitably some of the competition comes in-house. The Atmos AG is the closet alternative to the Aether AG, and is slightly more affordable at $270 for the 65-liter version. Both use the “AG” back panel, although the Atmos takes it a step further by using the suspended mesh along the hipbelt. As a result, it’s the better ventilator, but the Aether’s foam padding on the hipbelt and superior organization is best when carrying a heavy load. For the typical backpacker that isn’t carrying more than 40 pounds consistently, the Atmos AG is the bag we prefer (we rank it #1 on our backpacking pack review). But the Aether still is the more comfortable and feature-rich option.

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