The Osprey Stratos 36 is a ventilated and adjustable length backpack that is suitable for long day hikes, multi-sport adventures, and even lightweight backpacking trips. It has a suspended mesh back panel and seamless wrap-around hip belt that make it cool and comfortable to carry, with a lightweight frame that provides superb load transfer to your hips. While this combination makes it possible to carry heavy loads with ease, the Stratos 36 also has a thoughtful assortment of pockets and storage access methods that set it apart from similarly sized backpacks.
Note: This is a review of the current version of the Stratos 36. The latest model has a new ladder-style adjustable torso system and yoke with 4″ of adjustability and 40% more ventilation. The number of sizes was reduced from two in the previous version to one in the current model with a torso range of 18-22″ for men and 15″-19″ for the corresponding women’s Sirrus models.
Specs at a Glance
- Gender: Men’s (the corresponding women’s model is called the Osprey Sirrus 36)
- Volume: 36L (also available in 44L, 34L, and 24L sizes)
- Weight: 3 lbs 4.4 oz, actual (3 lbs 4.8 oz spec)
- Pockets: 9, plus the main compartment
- Access: Top lid, long side zipper, bottom pockets (2)
- Frame: Aluminum, wire perimeter
- Ventilated: Yes
- Adjustable Torso Length: Yes
- Hydration compatible: Yes
- Sleeping Bag compartment: Yes
- Rain cover included: Yes
- Max recommended load: 30 lbs
- One size w/ torso length of 18-22″
- Materials: Recycled 210d and 420d nylon w/ PFC & PFAS-free DWR
Backpack Frame and Suspension
The Stratos 36 is a ventilated and adjustable-length backpack with a seamless mesh back panel and hipbelt that provide a comfortable and back-hugging fit. Ventilated backpacks have a cavity located behind your torso that encourages airflow to keep you cooler and dry the perspiration that makes your shirt damp. They work pretty well and are a desirable feature on a day pack if you hike in hot or humid weather. On the Stratos 36, the mesh back panel is suspended over the backpack’s wire perimeter frame, creating a sort of trampoline that acts as a shock absorber to cushion your back and hips as you hike.
The mesh flows continuously from the back of the pack into the hipbelt, providing a body-hugging fit. Besides increased comfort and control, this helps eliminate any slippage of the hipbelt down your pants, so it stays on your hips for maximum efficiency and load transfer.
The Stratos 36 is also an adjustable-length backpack, which means you can dial it to fit your exact torso length, even if you normally fit between sizes. You do this by raising or lowering the shoulder straps in relation to the hipbelt so that the shoulder pads lightly touch the tops of your shoulders when the backpack is fully loaded. The goal is to let your hips and legs carry the majority of the weight in your backpack because they’re the strongest muscles in your body, while your shoulders keep the pack positioned close to your back and center of gravity.
The shoulder pads are connected together in the back to something called a yoke. The yoke is connected to the mesh back panel and integrated hip belt with using a ladder lock adjustment system (the previous model used velcro), so you can raise or lower the shoulder pads. Raising the pads makes the distance between the hip belt and the shoulder pads longer while lowering them makes the distance shorter.
The Stratos’ shoulder straps have the same comfortable and moisture-wicking padding as the hip belt. They’re also S-shaped and comfortable for men or women. The pack has load lifters that are anchored to the frame as well as the shoulder pads. These are used to pull the pack forward and into better alignment with your hips if it’s pulling you backward. The shoulder straps also have two hydration loops sewn to the front to capture a hose, and sternum straps that can be moved up and down on a “rail”, for ease of adjustment.
Backpack Organization and Storage
The Stratos 36 is loaded with nine pockets to keep your stuff organized, in addition to the main compartment which can be accessed from the top or through a side zipper. Having all these pockets and access methods makes the Stratos 36 an exceptional backpack if you need a pack for multi-sports adventures because you can separate the gear you need for different activities. There are:
- 2 pockets in the top lid
- 2 side water bottle pockets
- 2 hip belt pockets
- 1 front stash pocket
- 1 sleeping bag pocket
- 1 rain cover pocket
The Stratos 36 has a fixed top lid with a wide top pocket and a second zippered mesh pocket underneath, that has a key fob inside. The fact that the lid is sewn to the frame is good because it doesn’t droop awkwardly or slump sideways the way that some floating lids do on larger volume packs. The top lid pocket is large enough to store hats, gloves, maps, and navigation gear, while the mesh pocket underneath is good for storing your keys, wallet, and sundries where you can still see them when you open the pack.
There are two side mesh water bottle pockets that are deep enough to hold 1L Nalgene or Smartwater bottles. Both pockets have a compression strap that can run inside the pocket or on the outside if you find that easier to use. The side pocket mesh is reasonably durable but is not the finely woven mesh that Osprey uses on their more expensive, higher-capacity packs. That means that the Stratos 36’s mesh is likely to get ripped up if you catch it on a branch, but you can also easily patch the hole with Tenacious Tape (see How to Repair Backpack Mesh Pockets with Tenacious Tape.)
The hipbelt has two large zippered pockets that are big enough to store a Smartphone and several snack bars. They both have solid fabric faces, which is my preference because they’re more durable than pockets with mesh fronts and provide better protection for electronics from the weather or impacts.
There’s a separate sleeping bag compartment under the main pocket, which is accessed through an external zipper protected by a rain flap. The sleeping bag compartment is a floating shelf held in place by toggles, which can undo if you want to join it to the main compartment above to create a larger and continuous storage space.
The Stratos 36 comes with a rain cover which is stored in another pocket at the bottom of the pack. This pocket has a drain hole and is large enough that you can store a small water filter and rolled-up soft bottle, like a Platypus inside. That’s where I keep mine since the pack does not have a front stretch mesh pocket to store wet items.
There’s also a large pocket with a vertical zipper on the front of the pack which is good for storing a jacket or other items you want easy access to. I had a little trouble adapting to it since I’m so used to having an open mesh pocket on the front of a backpack. But this long pocket can be used in a number of ways that an open mesh pocket can’t be. For example, you can store all of your extra layers for a long hike including a puffy jacket, rain gear, hats and gloves; crampons or microspikes or both; climbing gear; backcountry ski gear; and emergency shelter, splint, and first aid kit, and so on.
In addition to all of these external pockets, the main compartment has a full-length hydration sleeve with a central hydration port, so you can run the hose down either shoulder pad. The main compartment can be accessed from the top, through a drawstring opening, or from the side, through a long side zipper. That side zipper is particularly handy when you want to pull something out of the bottom of the pack, like a warm jacket or your toilet paper, when it’s packed near the bottom of the main compartment. This is a pretty rare feature on a pack of this size but is super useful in colder weather.
External Attachments and Compression
The Stratos 36 has two tiers of side compression straps, which are good for securing tall objects like fishing rods the side of the pack. The top compression straps close with a quick-release buckle, which also makes it easier to attach snowshoes to the sides of the pack for winter hiking. The pack also has an ice ax loop with a shaft holder, the classic Osprey stow-and-go trekking pole holder, and a pair of sleeping pad straps below the sleeping bag pocket. It really is loaded with useful features.
The Osprey Stratos 36 is an exceptional backpack that can be used for day hiking, winter hiking, hut-to-hut trips, multi-sport adventures, and even lightweight overnight trips. While the Stratos has a comfortable ventilated and adjustable length frame and numerous pockets and organizational features, the thing that really stands out for me about this pack is its ability to carry heavy loads with relative ease. You can load it up with camera equipment, climbing gear, or winter traction aids and carry them with ease. If you’re looking for a versatile mid-size backpack that can be used year-round for a wide range of activities, I’d definitely recommend the Osprey Stratos 36.
Disclosure: The author purchased this backpack.
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