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Gregory Nano 18 H2O Review

A simple bag with a functional design and an excellent volume to weight to price ratio
Gregory Nano 18 H2O
Photo: Gregory
Best Buy Award
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Price:  $70 List | Check Price at REI
Pros:  Big volume, lightweight, great price
Cons:  Fewer pockets, lacking breathability
Manufacturer:   Gregory
By Tara Reddinger-Adams & Nick Bruckbauer  ⋅  May 10, 2021
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70
OVERALL
SCORE


RANKED
#7 of 13
  • Ease of Drinking - 20% 7
  • Ease of Filling - 20% 8
  • Comfort - 20% 6
  • 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 third 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.

Compare to Similar Products

 
Gregory Nano 18 H2O
Awards Best Buy Award   Best Buy Award  
Price $70 List
Check Price at REI
$90 List
Check Price at REI
Check Price at Backcountry
Compare at 3 sellers
$60.00 at Amazon$67.99 at Amazon
Overall Score Sort Icon
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Pros Big volume, lightweight, great priceComfortable, inexpensive, large storage volumeLightweight, large storage volume, solid hydration systemLightweight, sleek, solid performance in a minimalist pack, nice priceLightweight, hip belt pockets
Cons Fewer pockets, lacking breathabilityHeavy, small water capacityLimited organization, poor back panel ventilationAlmost no storage, shoulder straps are snug for users with wide shoulders and latsMinimal storage, lacks breathability
Bottom Line A simple bag with a functional design and an excellent volume to weight to price ratioA comfortable, affordable daypack, but is heavy and has a small water capacityAn all-around pack that successfully blurs the line between hydration pack and daypackNot just a classic, but THE Classic in minimalist packs and our recommendation for minimalists and those on a tight budgetA minimalistic pack best suited for those who are weight conscious and engaged in low exertion activities due to poor breathability
Rating Categories Gregory Nano 18 H2O REI Co-op Trail Hyd... Osprey Skarab 18 CamelBak Classic CamelBak Octane XCT 70
Ease Of Drinking (20%)
7.0
5.0
8.0
9.0
8.0
Ease Of Filling (20%)
8.0
8.0
7.0
8.0
7.0
Comfort (20%)
6.0
7.0
7.0
4.0
4.0
Storage (20%)
8.0
9.0
6.0
2.0
4.0
Weight (10%)
7.0
5.0
7.0
9.0
9.0
Ease Of Cleaning (10%)
5.0
8.0
7.0
6.0
6.0
Specs Gregory Nano 18 H2O REI Co-op Trail Hyd... Osprey Skarab 18 CamelBak Classic CamelBak Octane XCT 70
Pack Size (liters) 18 L 20 L 18 L 0.5 L 5 L
Bladder Capacity (liters) 3 L 2 L 2.5 L 2.5 L 2 L
Weight (measured) 25.6 oz 34.6 oz 25.5 oz 11.2 oz 17.6 oz
Weight (claimed) 18.4 oz 28.0 oz 17.6 oz 5.0 oz 10.0 oz
Waist Belt Removable 3/4" webbing Removable 3/4" webbing Removable 3/4" webbing None Padded with two zipper pockets

Our Analysis and Test Results

The Gregory Nano 18 H2O combines built-in 3-liter water capacity with a simplistic, lightweight, well-designed backpack. The main storage compartment is a simple storage design, making stowing large and bulky items easy. A lid pocket and side pocket provide secure storage for smaller items, and a side mesh pocket is large enough to hold an additional water bottle or even a light jacket. 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


This is a great pack for walks with our dog, who requires a little...
This is a great pack for walks with our dog, who requires a little bit of gear to help him along in his older age.
Photo: Tara Reddinger-Adams

Ease of Drinking


The Nano 18 H2O comes standard with the company's 3-liter 3D Hydro bladder, whose DryLock bite valve is held in place by a magnetic clip. Unlike some magnet bite valves that don't fit securely on their magnet, Gregory's magnetic clip works well and stays put. The built-in 3-liter bladder is tied for the highest capacity among the models we tested in our lineup and can pack enough water for most longer or more grueling adventures.


The DryLockbite valve is comfortable in the mouth and easy to drink from but does not have as high of a flow rate as other packs in our test. A small on/off switch is built into the bite valve, which works fine, but is not as smooth as others in its operation. Depending on the size of your torso, you may find the hose to be a bit short. On our 6'-3" tester, the hose was stretched across his chest and barely just reached the magnetic clip.

The hydration hose is rather short and just reached the magnet on...
The hydration hose is rather short and just reached the magnet on our taller tester.
Photo: Tara Reddinger-Adams

Ease of Filling


Compared to some of the other packs in our lineup, the Nano 18 H2Oreceives average scores when it comes to filling the bladder. The 3-liter 3D Hydro bladder has a circular opening, whose cap is easy to twist off but is smaller in diameter. The bladder is easy to fill from a sink or trailhead spigot but would be more challenging to fill from a lake or stream, or if you'd like to add large ice cubes (which is not something our testers do very much, but some folks may prefer).


The bladder has a few features that really make it stand out, one of which is a quick-connect located at the top of the bladder. This feature allows you to easily disconnect the hose before removing the bladder from the pack and reattach it after the bladder is loaded back into the pack. We found this design to be much easier to use than bladders that do not have a quick connection or those whose quick connect is located at the base of the bladder.

The integrated handle makes holding the bladder easy while filling.
The integrated handle makes holding the bladder easy while filling.
Photo: Tara Reddinger-Adams

Another great design feature that makes refilling the bladder much more efficient is its completely separate and easily accessible storage pocket. To remove the bladder, you need to unzip the pocket, detach the quick connect, unhook the bladder from the SpeedClip and pull it out. To replace the bladder, you need to reverse the steps. It's a very efficient and easy-to-use design and one of our favorites.

The bladder's quick connect is located at the top of the bladder...
The bladder's quick connect is located at the top of the bladder which makes removing and replacing the bladder a breeze.
Photo: Tara Reddinger-Adams

Comfort


The Nano 18 H2O has just enough rigidity and structure not to make it floppy on the back and is relatively comfortable for a sack-like pack. Even fully loaded with a first aid kit, extra layers, and a water bottle for the dog, the pack does not sag low on our back but is rather bulky.


The shoulder straps are comfortably padded and hug the body making the pack comfortable for hiking, but we found that it jostles around too much for singletrack mountain bike trails and is better suited for pavement rides around town.

This pack has great volume, but not enough support or structure for...
This pack has great volume, but not enough support or structure for mountain biking.
Photo: Byron Adams

One of the biggest drawbacks to the Nano H2O and similar packs is the lack of breathability, although it does breathe better than some other packs in our review. The pack sits directly against the back, allowing little airflow, leading to a hot and sweaty back. The hip belt is narrow webbing, and its adjustment is towards the back, which prevents long straps from dangling down in front of you and keeps them out of the way. There are no hip belt pockets on the Nano 18 H2O, but this is a trade-off as many comparable packs with hip pockets are considerably more money.

The back panel does not breathe the best, especially on hot hikes.
The back panel does not breathe the best, especially on hot hikes.
Photo: Byron Adams

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 no-frill main compartment, easy-to-use drawstring closure, large zipper pulls, separate bladder compartment, 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 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.

Click to enlarge
Click to enlarge
Click to enlarge

Weight


At a measured 25.6 ounces (1.6 pounds), the Nano 18 H20 lands in the middle of our test lineup when it comes to weight and is one of the lighter, higher volume backpacks in this category. We did test other similar lightweight designs, but they lacked the structure of the Nano, which prevents loads from sagging.


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.

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 with much wider openings. While not ideal, the bladder structure makes it possible to squeeze a cleaning brush inside, but this is not as efficient or effective as other models with a larger opening.


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. Our testers liked this feature a lot, as completely drying out the bladder after cleaning helps keep it fresh.

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

Value


The Gregory Nano H2O 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 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 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.

We were pleasantly surprised at how well the pack shed light rain.
We were pleasantly surprised at how well the pack shed light rain.
Photo: Tara Reddinger-Adams

Conclusion


The Gregory Nano 18 H2O offers great 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 for everyday use or your next adventure.

The Nano 18 H2O has a lot of volume for the money.
The Nano 18 H2O has a lot of volume for the money.
Photo: Tara Reddinger-Adams

Tara Reddinger-Adams & Nick Bruckbauer