The Osprey Exos 58 Backpack is one of the most popular backpacks used by thru-hikers and lightweight backpackers because it combines the organizational layout of a top-lid backpack, lightweight materials, and a rigid internal frame capable of hauling heavy loads.
The most notable change in the Exos 58 (last updated by Osprey in 2018) preserves those characteristics but eliminates the hip belt pockets and shoulder strap storage which many backpackers count on to store snacks, insect repellent, and electronics. Time will tell how backpackers will respond to the lack of these accessory pockets, but the Exos remains one of the few mainstream “ultralight class” backpacks available with a true frame and back ventilation, which are must-have features for a large percentage of backpackers.
Specs at a Glance
- Volume: 58L, also available in 48L and 38L
- Weight: 2 lbs 11 oz. (size medium, tested)
- Optional removable top lid: 5.4 ounces
- Torso: M: 18 – 21 inches
- Hip Belt: M: 27 – 48 inches
- Bear canister compatible: yes
- Maximum recommended load: 30-35 lbs.
Organization and Storage
The Osprey Exos 58 is very different from most ultralight backpacks because it’s configured with a floating top lid instead of a dry-bag style roll top. With two zippered pockets (one pocket on top and one inside), the floating lid lets you sandwich extra gear between the lid and the top of the pack’s main compartment so you can carry extra technical equipment or supplies that won’t fit inside your pack. Top lids are a great feature, especially when you need to carry bulky gear like rope coils or tent bodies that won’t fit into the main compartment of your pack. The extra top pockets also provide handy access to hats, gloves, snacks, and navigation gear.
If you don’t need the top lid on the Exos, you can remove it to save gear weight. This reduces the weight of a medium-sized Exos 58 by 5.4 ounces bringing it down to a very respectable 2 pounds 4.6 ounces.
There’s a nylon flap under the top lid that is permanently attached to the pack, what Osprey calls a FlapJacket, that covers the drawstring opening of the main compartment. When you remove the top lid, the FlapJacket is used to protect the main compartment from the rain in its stead. The rear of the FlapJacket also clips into the same rear straps and buckles used by the top lid so you’re not left with any extra straps or buckles to get in the way.
While the Exos 58, also has good open storage in the form of side and front mesh pockets, the main compartment is where the bulk of this pack’s capacity is. With close to 3500 cubic inches of room, you can put a ton of gear and food inside. Being a mainstream manufacturer, Osprey computes the volume of their packs using industry norms and only counts covered and zippered storage when they calculate backpack volume. If you are comparing the volume of the Exos 58 with a pack from a cottage backpack maker, be aware that they often add in open and closed pocket volumes so the Exos 58 may feel quite a bit larger.
The main compartment curves sharply inward to accommodate the shape of the ventilated frame but can make it difficult to locate gear because you need to reach around the curve to get to it. When packing the Exos 58, you also need to position that the heaviest items as close to your back as possible, otherwise the pack has a tendency to pull you backward and off-balance. This is a common issue with ventilated backpacks, and while pulling the Exos’ load lifters forward can help reduce the back-tilt, the backward pull is quite noticeable when the pack is heavily loaded.
With the exception of a hydration pocket, hang loop, and top compression strap, there’s nothing inside the Exos 58 main compartment like a sleeping bag compartment or interior pockets to break up the seemingly cavernous space. Still, it’s easy to see inside the main compartment because lightly colored fabric panels help channel light to the pack’s interior.
In addition to the main compartment, the Exos 58 has two stretch side mesh pockets which can be used to store water bottles. The mesh is not strong enough for off-trail travel and I would recommend you stay on trails with this pack in order to keep the pockets from tearing. Each pocket is reinforced with solid fabric on the bottom for better durability and has a holster-style opening cut in front, which lets you position bottles sideways so you can pull them out and replace them when on the move. I’d just caution against using tall bottles or packing small items in the side pockets because they fall out of the holster sized water bottle holes.
There is also a front mesh shovel pocket on the back of the pack which is useful for carrying items that you want easy access to, without requiring that you stop and open your backpack. I can’t live without a mesh pocket like this and use it to stuff light layers and snacks that I want easily accessible during the day.
External Attachment Points and Compression System
The Osprey Exos 58 has one Z-style side compression strap on each side of the pack. The strap can be threaded in front of or through the side water bottle pocket, which is handy because they won’t get in the way if you run them outside the pocket. Still, I’m not a huge fan of the Z-style threading pattern because I think it makes it difficult to strap bulky gear like snowshoes to the side of a pack.
But don’t let the Z-style straps deter you from rigging up two horizontal compression straps instead. One of the great things about the Exos 58 is the distribution of gear loops around the perimeter pockets, the pack bag seams, and even the top lid, making it easy to rig up your own custom compression system with an extra cord lock and some guyline or a piece of webbing.
The other key attachment point on the Exos 58 is the sleeping pad strap on the bottom of the pack, a feature which has largely disappeared from the lightweight backpacking market. While the strap is optional and can be removed, it’s super handy to have if you’re a thru-hiker, hammock camper or winter camper and carry a bulky foam pad to sleep on at night.
Backpack Frame and Suspension
The Osprey Exos 58 is a ventilated “trampoline-style” backpack. Breathable mesh is suspended in front of the back panel creating a ventilated space behind your back that’s designed to evaporate sweat before it can soak your shirt. The mesh is tightly stretched across the aluminum frame, hence the name trampoline, which also serves to anchor the hip belt and load lifters.
The aluminum frame on the Exos 58 is the secret sauce that “makes” this pack. It’s super lightweight and stiff, providing great load transfer to the hips, so you can really load up this pack and still get a very comfortable carry. The nice thing about an aluminum frame is that the torso won’t collapse, causing the torso length to shorten when you load the pack to capacity, which can be an issue with other lightweight packs.
The shoulder straps and hip belt are both covered with a stretchy mesh fabric that is soft and helps wick moisture to prevent rubbing and chafing. While they’re both well padded so they conform to the shape of your collarbone, shoulders, and hips and don’t slip.
But there’s one thing about the Exos 58 that I don’t particularly like and that’s the length of the hip belt, which I think is too short. There is simply no way that the size medium Exos 58 fits someone with a 27-48″ waist. I think a maximum of 38″ is a more realistic upper limit.
If you buy an Exos 58 and the hip belt padding only wraps around the back of your hips, which happens when the hip belt is too short, you won’t be as comfortable or get the load transfer you should expect. This isn’t just a sizing issue with the Exos 58, but a sizing issue that I repeatedly encounter with Osprey Packs that don’t have adjustable hip belts. If the front padded portion of the Exos hip belt doesn’t wrap around the front of your hip bones (see How should a Hip Belt Fit?), get a larger size. If that still doesn’t fit, buy a different backpack.
- Lightweight and high-capacity (58 L)
- Easy to remove top lid w/ lightweight replacement lid
- Optional sleeping pad straps on the bottom of the pack
- Lightweight perimeter frame provides great load transfer and control
- Lightly colored fabric strips improve main compartment visibility
- Lots of external attachment points all around the pack
- The hip belt is not adjustable
- No hip belt or shoulder strap pockets
- Holster-style cutouts in the side mesh pockets are less secure for storing small items
- Single Z-style side compression strap can be awkward to use
|Make / Model
|Gossamer Gear Mariposa 60
|Granite Gear Crown 3 - 60L
|Roll top, Top lid
|Granite Gear Blaze 60
|Roll top, Top lid
|Hyperlite Mountain Gear Southwest 55
|Osprey Exos 58
|Top lid, speed flap
|Gregory Focal 58
|Top lid, speed flap
|Zpacks Arc Blast 55
|Mountain Laurel Designs Exodus 57
|Mountainsmith Scream 55
|Seek Outside Gila 3500 (57L)
|Roll top, side zipper
|Sierra Designs Flex Capacitor
|Elemental Horizons Kalais
The Osprey Packs Exos 58 Backpack is a top-loading backpack that’s easy to configure for many different kinds of hiking and backpacking trips. Weighing just 2 pounds 11 ounces, it boasts a stiff aluminum frame and ventilated suspension that provides excellent comfort and control for loads up to 30-35 pounds. If you want a large but lightweight (58L) backpack with a real frame and a top lid, the Exos 58 is a great choice. Sizing can be a little tricky however since the hip belt lengths available are tied to the torso length of the pack. If the Exos 58 fits you, great. It’s an excellent backpack. If it doesn’t fit, give it a pass.
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