Osprey Dyna 6/Duro 6 Review

Today is the day I finally tell you about the Osprey Dyna 6 and Osprey Duro 6 ($110) hydration packs. Why finally? I spent nearly a year testing this running vest! What this means for you is that I have put this hydration pack through the ringer, on everything from my daily runs to bigger weekend adventures. In early March of 2020, I was lucky enough to run an actual 50-kilometer race–remember those?–wearing the Osprey Dyna 6 hydration pack. It proved to be a reliable and comfortable piece of gear on a really tough day of racing as well.

The Dyna 6 is the women’s-specific version and the Duro 6 is the men’s. The features are the same in both models, though the fitments are optimized to women’s and men’s body frames, respectively.

Despite owning a few pricier hydration packs for running with similar storage capacity, I tend to reach for this pack. I have enjoyed using it during each of the seasons and all of the elements. Read on to learn why.

Osprey Dyna 6 hydration pack front view

The Osprey Dyna 6 hydration pack. All photos: iRunFar

Osprey Dyna 6/Duro 6 Construction and Fit

In the Osprey Dyna 6 and Osprey Duro 6 hydration packs, Osprey describes the innermost construction as a “breathable mesh wrap” that is “soft and irritation-free” upon contact. I agree with this description 100%. This running vest is very comfortable whether worn over wintry layers or on a scorching summer’s day over just a sports bra.

The exterior layers are a combination of ripstop fabric and a stretch mesh. I appreciate packs that combine a more forgiving stretch material and a durable fabric–in this case ripstop–as it boosts my confidence in the vest’s ability to last a long time, which is important when investing in any piece of gear.

The Osprey Dyna 6 and Duro 6 running vests sit high on the back.

Interestingly, the Dyna 6 and Duro 6 are available in two storage capacities with a six-liter storage capacity in the larger size of both packs and five liters in the smaller size of both. The sizing itself is also interesting. The Dyna 6 comes in 2 sizes, a women’s extra small/small (31 to 37 inches at the chest) and small/medium (35 to 41 inches at the chest). The Duro 6’s sizing is men’s small/medium (34 to 40 inches at the chest) and medium/large (39 to 45 inches at the chest). I find it odd that Osprey overlaps sizing in the two Dyna 6 women’s sizes, and doesn’t accommodate for a size large.

For reference, I’m 5 foot, 3 inches tall with a small chest and broad shoulders. I typically wear a women’s size small or 4 in tops. I tested the small/medium size, though it’s possible I would have also fit the extra small/small. That said, I would not change my size choice, because I really like the way this size fits over several winter layers and when adjusted down for less clothing in the summer. Based on my fit experience, it wouldn’t surprise me if women who generally shop size large would also find the small/medium version of this vest to be comfortable and highly adjustable.

Speaking of adjustments, there are two elements on this hydration pack that allow the wearer to ensure a snug fit. The first are the chest straps, which might be one of my absolute favorite features of this vest. They are ridiculously easy to tighten, loosen, and move up and down. They offer a great range for various shapes and sizes. The ease of adjustment experienced on the chest straps cannot be said for all vests, especially when working with cold fingers or when filled to capacity. The second adjustment can be made along the sides via a left and right strap that secure the vest snugly against the ribs.

Compression straps on the outermost back pocket can also be used to, you guessed it, compress the contents of the larger back compartments which certainly helps keep the vest secure and free of unwanted movement while running. These compression straps are not as easy to reach with the pack on and so I don’t use them to adjust the overall fit/feel of the pack on the go.

Osprey Dyna 6 hydration pack side view with pockets

The Osprey Dyna 6 hydration pack showing a number of pocket options on the side and back of the pack.

Osprey Dyna 6/Duro 6 Storage and Hydration Options

The Osprey Dyna 6 and Osprey Duro 6 hydration packs are made to carry a lot of stuff, including layers, snacks, emergency items, poles, traction, and more. I often find myself thinking, Should I bring (insert any item here)? With this running vest, you have plenty of room to include those just-in-case items you may not normally carry with you if you were dealing with limited space.

The Osprey Dyna 6 and Duro 6 come equipped with a 1.5-liter reservoir, specifically a Hydraulics LT 1.5-Liter Reservoir with QuickConnect. The pack also accommodates for a 250-milliliter soft flask in both of the extra large front mesh pockets. While these aren’t included, I already own Osprey’s soft flasks and can confirm these fit well in the noted storage pockets. There is a bit of wrestling involved in getting the soft flasks into these pockets as their mesh is more restrictive than other brands I’ve tested, but with a little finagling all is fine. If you prefer to run with soft flasks only and skip the reservoir, this could be a deterrent for you, but I seldom bring the soft flasks along and find these stretch mesh pockets to be useful in storing nutrition and my cell phone, which is approximately 6 inches tall and 3 inches wide.

When it comes to pockets, there are plenty to go around and they all get the job done. We’ll start with the front of this running vest. As previously mentioned, there are two extra large mesh pockets on the front of the vest. An additional smaller mesh pocket can be found on top of these pockets that are about half as tall and hold about half the capacity. These smaller pockets are great for smaller items like nutrition wrappers and chapstick. You can easily use these to store your nutrition if the larger pockets are carrying soft flasks. As with the extra large mesh pockets, the smaller mesh pockets are also a bit restrictive. This is due once again to the material used. I tend to prefer this as it yields confidence that my items will remain secure in these pockets regardless of the activity.

The front of the hydration pack also contains a long zippered pocket on the left side that’s large enough to hold a cell phone, keys, and/or identification. You’ll find an emergency whistle hidden in the top of the extra-large mesh pocket on the right-hand side of the pack as well. Essentially, the front of this pack has everything you need and nothing that you don’t. Just how I like it! No extras but there is plenty of room to get everything you need for a day on the trail in a place that makes sense and that’s easily accessible.

Osprey Dyna 6 hydration pack with pockets and compression straps

The back of the Osprey Dyna 6 hydration pack with its 4 pockets on the back and compression straps.

The back of the Osprey Dyna 6 and Duro 6 hydration packs are home to a number of useful compartments, the first being the hydration pocket. This is a zippered pocket that also contains a clip and loop to ensure your reservoir doesn’t slide down as it empties. As with most packs, you have the option to thread your bladder’s hose over both the right and left shoulders.

There are 2 additional zippered compartments on the back of the running vest. One waterproof, zippered pocket is a shallow storage option for items like keys, phones, wallets, and similar, while the other zippered pocket runs the length of the back of the pack and has the capacity to carry packable layers, an emergency blanket, headlamp, and more. These pockets are created with a ripstop material that is not stretchy, so if you’re looking to stretch the limits of what they can hold, you won’t get far. However, they are already constructed to hold a ton and if you’re hoping this pack carries more, then you should be in the market for a backpack designed for more of a fastpacking experience.

There are 2 other storage options at the back of the Osprey Dyna 6 and Duro 6 hydration packs. One is a compression pocket that is the outermost layer of the pack and accommodates a faster/more accessible storage of layers that you may be taking on and off with regularity or something like a dog leash. I use this pocket for both with regularity. There are also 2 angled mesh pockets on each side of the back of this hydration vest. I almost always use these for glove storage in cooler temperatures as they’re easy to reach back and grab when I need them and store when I don’t.

Other features of the Dyna 6 and Duro 6 worth noting are the bungees that allow for trekking-pole storage on the back of the pack in conjunction with the 2 angled mesh pockets. The bungees are on the top of each shoulder and work well for me. There is also a small magnet on the front of the pack and the tube of the reservoir that secures the tube to the front of one of the sternum straps. I have come to really appreciate this little feature over time.

Osprey Dyna 6 hydration pack side view showing its fit

Another side view of the Osprey Dyna 6 hydration pack showing its fit high on the torso.

Osprey Dyna 6/Duro 6 Overall Impressions

Ultimately, I really like the Osprey Dyna 6 and Osprey Duro 6 hydration packs for long days of adventuring. This running vest does what it’s designed to do with just enough of everything you want and nothing more. I prefer the materials used in the construction of these packs and that they make for a comfortable experience across all seasons and weather. I also really like the way it sits on my upper body. It feels very secure without being restrictive and is comfortable for hours on end. And because it aesthetics matter to some, I like the way this vest looks when I spot another runner wearing it. Oh and helloooo, that $110 price point is pretty awesome!

This is the second iteration of the Osprey Dyna and Duro series that I’ve owned and worn pretty religiously. That’s gotta’ be saying something. It has demonstrated itself to be a very reliable piece of gear in my trail running quiver and I expect to be reaching for it for many adventures to come.

Call for Comments

  • Are you running in this version of the Osprey Dyna 6 and Osprey Duro 6? If so, what do you think overall?
  • What do you think of the high-torso fitment of this pack?
  • How do all of the storage pockets work for you? Which do you like more and less?

[Editor’s Note: If you’re affiliated (i.e., an employee, ambassador, etc.) with a brand, please share your relation in each of your comments on this article. Thanks!]

Casey Szesze

resides in Sisters, Oregon. An expert in multi-tasking, Casey works full time as both a digital marketing consultant and the chief operating officer of her household, which includes three kids and a dog. You can find Casey on the local trails near her home and she always appreciates trailside high-fives and good vibes.

There are 4 comments

    1. Meghan Hicks

      Antonela, it sounds like you are a size small/medium, but be sure to check the sizing on it to make sure your bust size is in the range. The small/medium’s chest size range is 34 to 40 inches.

  1. Patrik Puhala

    great review! I love these packs. They also tend to hug the body better than most vests and fit really well. The rear compression straps really lock down the back pockets and avoid any bouncing around even on fast descents. My favorite pack. Its even lasted longer than any other vest I’ve used!

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