

Switchback Travel
Switchback Travel
Price:Â $270
Weight: 4 lbs. 9 oz. (men's medium)
Fabric:Â Nylon (100D x 630D)
Capacities:Â 50, 65L
What we like: Fantastic ventilation, close and supportive fit, and durable build.
What we don’t: No zippered access to the main compartment; hipbelt can cause discomfort.Â
See the Osprey Atmos AG 65Â Â See the Women's Osprey Aura AG 65
One of the few downsides in the industry-wide transition to internal-frame packs is ventilation. Enter the Atmos line from Osprey, and more recently, the Atmos AG pack. This bag has been designed from the ground up to keep your back dry without sacrificing load capacity and comfort. After a number of backpacking trips, including multiday treks in hot weather in Utah and a late winter trip into the Grand Canyon, we’ve come away very impressed. Not only does the pack offer excellent ventilation, but it’s a standout performer in nearly every category. Below are our thoughts on the Atmos AG's carrying comfort, weight, organization, ventilation, fit, and more. To see how the Atmos stacks up, see our article on the best backpacking packs.
When I slid on the Osprey Atmos AG 65 for the first time, I was struck with how well it fit. The mesh backpanel and hipbelt naturally want to fold inwards, which means the pack practically hugs you. It makes a strong first impression, and we’ve found it to be very comfortable even after logging serious miles on a number of overnight and extended trips (loads varied from around 25 to 40+ pounds). Even though the sculpted backpanel does pull the load a little bit away from you, we never felt any disconnect, nor the sensation of the weight pulling us backwards (although it did take one of our testers some time to get used to).
But despite the Atmos’ overall comfort, the stiff hipbelt raised some concerns. During an extended trip along the Grand Canyon’s Escalante Route, one tester reported notable discomfort at the edges, which roll slightly inwards, after only a day wearing the pack. Compared to the shoulder straps and the rest of the belt, this area is relatively unpadded, creating pressure points that continued throughout the rest of the journey. Some might not experience the same issue depending on where the pack falls (and there’s plenty of room for adjustment), but it was noticeable enough for us to call out directly.
Finally, the Atmos AG is not our absolute favorite pack for carrying a heavy load (45-plus pounds)—that honor is reserved for options like the Gregory Baltoro, REI Co-op Traverse 70, and Osprey’s own Aether AG. But the Atmos holds its own on multiday treks. Even on trips where we’ve brought along extra water, camera equipment, or items for gear testing, its sturdy frame has kept us quite comfortable. This is all despite using a suspended mesh hipbelt design rather than thick foam—a testament to the Anti-Gravity technology.
At 4 pounds 9 ounces in a medium frame, the Osprey Atmos AG is competitively lightweight for what we consider a luxury pack. Construction and features vary widely even among backpacks of a similar capacity: on one end of the spectrum are the ultralight models (around 2-3 pounds) that only have a couple pockets and are made with very thin materials. At the other are traditionalist packs with premium features and thick, durable fabrics, but the weights often creep towards 5 pounds. The Atmos AG falls towards the premium side, although at 4 pounds 9 ounces, it’s not excessive (the popular Osprey Aether AG 60 weighs 5 lbs. 2.4 oz.). Others in this category, including the REI Traverse 70 (4 lbs. 14 oz.) and Gregory Baltoro 65 (4 lbs. 13.4 oz.), also outweigh the Atmos. For those looking to trim weight, you can leave behind the top lid and use the attached “FlapJacket” to cover the main compartment. In the end, considering how well it can carry a load exceeding 40 pounds, we feel the weight is reasonable for those who value carrying comfort.Â
If organization is a priority, the Osprey Atmos AG 65 is well-appointed with plenty of pockets, lash points, and gear loops. To start, you get the standard array of two zippered pockets in the top lid, two mesh water bottle holders, a sleeve for a water reservoir, and a very large mesh stuff-it pocket along the front of the pack. There’s also a dedicated sleeping bag compartment with its own zipper at the base of the pack, which is really helpful for staying organized and often omitted in lighter designs. And when the terrain gets tricky, a trekking pole attachment point along the shoulder strap makes it easy to free up your hands.
The features we’ve found most convenient are the zippered pockets that flank the large mesh front pocket—they’re quite large and can swallow bulky items like a water filter, rain jacket, or extra fuel canisters—and the two hipbelt pockets. These too are on the big side and should easily accommodate a modern smartphone in a case (we were even able to fit a point-and-shoot camera in its case).
One area for improvement would be a zippered access into the main compartment. The Atmos has a standard top-loader design, which makes it a pain to dig through and find an item that’s hidden deep inside, although the zippered sleeping bag compartment at the bottom helps some. Adding another zipper would tack on some ounces to the total weight, but we’ve come to appreciate the quick and easy access to the main compartment you get with this feature.
The big news here is along the back—one large suspended mesh panel covers the entire backpanel and hipbelt of the Atmos AG. Dubbed Anti-Gravity (hence the AG in the name), even the shoulder straps have the same open webbing. Simply put, we haven’t worn a pack that encourages this much airflow. And expanding the concept to the hipbelt is seamless. If your number one consideration in buying a backpacking pack is ventilation, the Osprey Atmos AG is the one.
What takes the Atmos’ ventilating design from merely good to great is the fact that it doesn’t compromise the rest of the backpack. It’s simply another quality Osprey item: the pack can haul a multi-day load in comfort, has thoughtful organization, and is made with durable materials that haven’t shown any signs of excessive wear over extensive use. The curved backpanel, which creates the open space for air to reach your back, does cut into the main compartment a little, but it’s still easy to fit large items like a standard bear canister inside.
The Osprey Atmos AG 65 is offered in three different sizes (small, medium, and large), and we’ve found it very easy to dial in a nice fit. As mentioned above, the bag conforms nicely to your back, and adjusting the shoulder straps is as simple as sliding them up and down along the backpanel. Additionally, the light foam padding along the hipbelt can be moved in or out to increase comfort. We had no issues sharing our medium-sized pack between two testers with 18- and 21-inch torsos.
In addition to the 65-liter pack tested here, Osprey also makes the Atmos in a smaller 50-liter version. Compared to the 65, the Atmos AG 50 costs less at $240 and shaves off around 6 ounces of weight (in a size medium). However, it retains all the storage options as its larger sibling, as well as features like the Anti-Gravity mesh backpanel, removable lid, lower sleeping bag compartment, and well-padded hipbelt and shoulder straps. In the end, we think the 65 is the more versatile size and worth the extra $30, but for shorter trips and those used to packing light, the Atmos AG 50 is a nice way to save.
We tested the men’s Atmos AG, but Osprey also makes the pack in a women’s version, the Aura AG. Like the Atmos, the Aura comes in 50 and 65-liter capacities, but it offers a female-specific fit and different color options (for more, see our in-depth Aura AG review). Importantly, the two designs share the Anti-Gravity system and key features such as the pocket layout, high-quality fabrics, and attachment points for trekking poles and an ice axe.
Pack | Price | Weight | Fabric | Capacities | Access | Pockets |
---|---|---|---|---|---|---|
Osprey Atmos AG 65 | $270 | 4 lb. 9 oz. | Nylon (100D x 630D) | 50, 65L | Top | 8 exterior |
Osprey Aether AG 60 | $290 | 5 lb. 2.4 oz. | Nylon (210D & 500D) | 60, 70, 85L | Top, front | 7 exterior |
Gregory Baltoro 65 | $300 | 4 lb. 13.4 oz. | Nylon (210D) | 65, 75, 85L | Top, front | 9 exterior |
REI Co-op Traverse 70 | $249 | 4 lb. 14 oz. | Nylon (200D & 420D) | 35, 70L | Top, front | 11 exterior |
Osprey Rook 65 | $165 | 3 lb. 8.3 oz. | Nylon (600D & 100D) | 50, 65L | Top | 5 exterior |
As a high-capacity and well-ventilated pack, it’s tough to be beat the Atmos AG. Osprey’s own Aether AG 60 shares the same Anti-Gravity backpanel, but it’s aimed more toward hauling heavy loads and even light mountaineering, with a heat-moldable foam hipbelt that adds extra support. The Aether also adds features like a J-shaped zipper to access the main compartment and a removable top lid that converts into a handy daypack for summit pushes or other outings from camp. You pay the price in both weight (5 lbs. 2.4 oz.) and cost ($290), but the Aether has its place for those shouldering serious weight or who like the extra features. In most other cases, we’d go with the lighter Atmos.
For carrying a fully loaded pack, the venerable Gregory Baltoro 65 is another attractive option. With the Baltoro, you get zippered access to the main compartment (a notable omission with the Osprey), as well as generous padding, an integrated rainfly, and excellent organization. However, the feature-rich design does add some weight at 4 pounds 13.4 ounces. Both are capable choices for long days on the trail, but we’d break it down as follows: if you prioritize comfort above all else, get the Baltoro. But the Atmos gets the nod as the lighter and better all-around option for most overnight and multi-day trips.
REI Co-op's Traverse 70 has long been a favorite of ours, and their most recent version uses a creative compression system for keeping the load close to your back (see our in-depth review here). In addition, you get good organization, impressive support, and solid comfort overall—all for about $20 less than the Atmos. That said, the Traverse’s backpanel isn’t quite as comfortable and the pack weighs an extra 5 ounces, which is significant. And if you prioritize ventilation, the Traverse falls short of the Atmos in that regard.
Finally, Osprey offers another in-house alternative to the Atmos in their budget-friendly Rook 65. On paper, there’s a lot to like about the Rook: it comes in at a reasonable $165 (over $100 cheaper than the Atmos), weighs over a pound less at 3 pounds 8.3 ounces, and is more robust with a 600/1000D polyester and nylon build. But after taking the Rook on the same early-season trip into the Grand Canyon, we came away unimpressed. Specifically, we found the pack to be noticeably lacking in comfort and overall organization—two areas where the Atmos excels. In the end, the Rook is a fine entry-level pack, but for those who plan on getting out a lot, we recommend spending up for the more comfortable and feature-rich Atmos.
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