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Gregory Nano 18 H2O Review

An excellent volume to weight to price ratio
Best Buy Award
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Price:  $70 List | $69.95 at REI
Pros:  Big volume, lightweight, great price
Cons:  Fewer pockets, average hydration performance
Manufacturer:   Gregory
By Nick Bruckbauer ⋅ Review Editor  ⋅  May 7, 2020
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72
OVERALL
SCORE


RANKED
#4 of 14
  • Ease of Drinking - 20% 7
  • Ease of Filling - 20% 8
  • Comfort - 20% 7
  • Storage - 20% 8
  • Weight - 10% 7
  • Ease of Cleaning - 10% 5

Our Verdict

A huge 18-liter storage volume and 3-liter water capacity combined with a tiny price tag earn the Gregory Nano 18 H2O our Best Buy Award for the second consecutive year. A gaping main storage compartment, two external zippered pockets, a water bottle sleeve, and a handful of tie-down loops make this an ideal pack for all-day adventures that can also double as a gym bag, school or work backpack, or carry-on for your next weekend flight. Though it lacks some higher-end features found on pricier models like hip belt pockets and a super breathable back panel, the Nano is a tremendous value at nearly half the price of many competitors.

New Colorways
Since we got our hands on this hydration pack, Gregory added some new colorways, but the change is limited to aesthetics.

Compare to Similar Products

Our Analysis and Test Results

The Gregory Nano 18 H2O is a newer offering from Gregory, combining a built-in 3-liter water capacity with a lightweight, well-designed backpack. This pack has a simple yet effective storage design with a large main compartment, two external zippered pockets, and has a separate easily accessible sleeve for the hydration system. This product scores well across all of our rating metrics, and combined with one of the lowest prices in our lineup, takes home our Best Buy Award once again.

Performance Comparison


The Nano is ready to tackle whatever challenge you throw at it.
The Nano is ready to tackle whatever challenge you throw at it.

Ease of Drinking


The Gregory Nano 18 H20 is equipped with a massive 3-liter 3D Hydro hydration bladder from Gregory that delivers water through a DryLock bite valve secured by a magnetic attachment clip. We've found that these magnetic attachment clips can sometimes be a bit of a nuisance to keep properly attached, but we can report the magnet on this pack worked for us without any problems. The built-in 3-liter reservoir is tied for the highest capacity among the models we tested in our lineup and is able to pack enough water for most longer or more grueling adventures.


This model scores adequately in our drinking ratings, but it doesn't deliver the goods quite as efficiently as some of the higher-ranked hydration systems that we've tested. Gregory's DryLock bite valve doesn't have the fastest flow rate in our real-world experience, we do appreciate how the shape of the valve makes finding and chomping down on the correct spot easy, helping achieve optimum drinking efficiency.

Rehydrating with the Nano 18 H2O.
Rehydrating with the Nano 18 H2O.

Ease of Filling


Compared to some of the other packs in our lineup, the Nano 18 H2O receives average scores when it comes to filling up the bladder. The 3-liter 3D Hydro water bladder is one of the few models in our lineup equipped with a circular opening. While this design was certainly adequate for filling in our kitchen sink, it might prove to be a little more challenging if you need to fill up from a different water source, or if you'd like to add large ice cubes (which is not something our testers do very much, but some folks might prefer).


Another minor drawback is that the Nano's hydration system does not include quick-release drinking hose, meaning you'll need to either remove the entire drinking hose system to refill the bladder or attempt to refill the bladder while it's still attached to the pack. We found this to be only a minor inconvenience though since the hose routing is easy to manipulate through the pack.

The 3D Hydro bladder in the Nano 18 is simple to fill in the kitchen sink  but the circular opening may be challenging under more difficult circumstances.
The 3D Hydro bladder in the Nano 18 is simple to fill in the kitchen sink, but the circular opening may be challenging under more difficult circumstances.

One great design feature that makes refilling the bladder much more efficient is its completely separate and easily accessible storage pocket. By simply unzipping the oversized pocket, unhooking the bladder, and freeing the drinking hose from the adjacent opening, you're ready to fill 'er up. Replacing the refilled bladder in the same location is similarly efficient.

Though it lacks a quick-release drinking hose  the separate bladder pocket with a generous opening helps simplify removal of the bladder.
Though it lacks a quick-release drinking hose, the separate bladder pocket with a generous opening helps simplify removal of the bladder.

Comfort


The Nano 18 lands among the upper portion of the lineup in our comfort rankings, coming equipped with comfortably-padded shoulder straps and a back panel that nicely hugged our body when fully loaded.


The drawback to the cushy support provided by the Nano is that the back panel is lacking in breathability. While it certainly gave us a comfortable hug, it did so a little too closely without much ventilation, leading to a hot and sweaty back after extended use. Another minor drawback is that the hip belt consists of simple webbing straps, which weren't as comfortable under heavier loads as models with more substantial hip belt padding. However, competitor models with fancier hip belts typically have list prices almost double that of the Gregory Nano, so we think that this might be a fair tradeoff if you're looking to save some money.

While the padded back panel and shoulder straps are quite comfortable  there isn't much ventilation  and the waist belt isn't very supportive.
While the padded back panel and shoulder straps are quite comfortable, there isn't much ventilation, and the waist belt isn't very supportive.

Storage


With 18 liters of storage space, the Nano 18 H2O is among the largest packs we've tested in this category. Of the handful of larger volume hydration pack models in our lineup, the Nano has our favorite storage design, with a large main compartment with drawstring closure, a separate hydration bladder sleeve, and two external zippered pockets. We like the simplicity and convenience of this design and appreciate how it balances bulky item storage and smaller item organization.


While the sizeable overall storage volume is convenient, the Nano does lack some of the organizational features for smaller pieces of gear, like what is found on some pricier fully-featured packs. If you don't need quite so much organization, and just want a way to keep your bulky items separate from your keys, wallet, and phone, we think the Nano 18 H2O can do the job admirably. For longer excursions, the Nano even has an additional external water bottle sleeve and a handful of tie-down loops.

The main compartment on the Nano 18 H2O has tons of volume.
The Gregory Nano has one of the best volume-to-weight ratios in our lineup.
The exterior zippered pocket on the top lid has room to keep all your essentials within reach.

Weight


At a measured 1 lb 9.5 oz, the Nano 18 H20 lands in the middle of our test lineup when it comes to weight, but is one of the lightest higher volume backpacks in this category. While there are certainly some lighter offerings in the lineup like the ultra-light minimalist designs, none of these other models offer the same storage or comfort provided by the Nano.


Conversely, while some other packs have more luxurious features like built-in insulation or padded storage compartments, those features certainly come at a weight premium. For a great balance performance and weight, the Gregory Nano is tough to beat.

On the move with the Gregory Nano hanging tight.
On the move with the Gregory Nano hanging tight.

Ease of Cleaning


As you'd likely imagine, with a smaller circular opening, the 3D Hydro bladder on the Nano 18 H2O is not as easy to clean as other models in our lineup with much wider openings. While not ideal, the structure of the bladder does make it possible to squeeze a cleaning brush inside, but this is not as efficient or effective as the fully opening capabilities of many other models.


One nice feature on the Nano not found on other packs is that it includes a Quick Dry Hanger to make sure that the bladder can sufficiently air out. Most of our testers liked this feature a lot, as completely drying out the reservoir after cleaning helps keep it fresh.

The Quick Dry Hanger on the Gregory 3D-Hydro systems is a nice touch to help empty and dry out the bladder.
The Quick Dry Hanger on the Gregory 3D-Hydro systems is a nice touch to help empty and dry out the bladder.

Value


The Gregory Nano is one of the lightest full backpack-style hydration packs we tested, and with a huge 18-liter storage volume, 3-liter water capacity, low weight, and surprisingly low cost, it provides a tremendous value and walks away with our Best Buy Award. While you may sacrifice some top of the line features, you'll likely be paying half the price of some of the top-end models in our lineup. For most people looking for a great all-around hydration pack that won't break the bank, the Nano 18 H20 should be on your list.

The Nano 18 is capable of keeping up on your next adventure.
The Nano 18 is capable of keeping up on your next adventure.

Conclusion


The Gregory Nano 18 H2O offers amazing performance and value for a fraction of the price, taking home our Best Buy Award. A simple yet effective design, solid construction, and lightweight materials make this a solid pack that can take you on your next adventure.

Nick Bruckbauer