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 scored well in all of our testing categories, and combined with one of the lowest prices in our lineup, takes home our Best Buy Award.
The Nano was ready to tackle whatever challenge we threw at it.
Ease of Drinking
The Nano 18 is equipped with a massive 3-liter 3D Hydro hydration bladder that delivers water through a DryLock bite valve attached to a magnetic attachment clip. While this model scored adequately in our drinking ratings, it doesn't deliver the goods quite as efficiently as our top-rated drinking system, the CamelBak Crux with their Big Bite valves. For a similar sized daypack with the top of the line drinking system, consider the CamelBak Cloud Walker 18.
While Gregory's DryLock bite valve didn't have the fastest flow rate in our real world experience or during our in-home tests, we did appreciate how the shape of the valve made finding and chomping down on the correct spot easy, helping achieve reasonable drinking efficiency. Still, our testers prefer the greater flow rate of the CamelBak Big Bite valves, and recommend switching out the mouthpiece if you love this pack but want to deliver a faster flow rate.
Rehydrating with the Nano 18 H2O.
Ease of Filling
Compared to some of the other packs in our lineup, the Nano 18 H2O received 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 hydration system does not include quick release tubing, meaning you'll need to either remove the entire tubing system to refill the bladder or attempt to refill the bladder while still attached to the pack. We found this a minor inconvenience though since the tubing routing is easy to manipulate. If you're interested in a higher end system with convenient quick release tubing, check out the Syncro 12 or Duthie A.M. 10.
The 3D Hydro bladder in the Nano 18 was simple to fill in the kitchen sink, but the circular opening may be challenging under more difficult circumstances.
One great design feature that made refilling the bladder more efficient is its separate and easily accessible storage pocket. By simply unzipping the oversized pocket, unhooking the bladder, and freeing the drinking tube from the adjacent opening, you're ready to fill 'er up. Replacing the refilled bladder in the same location was similarly efficient.
Though it lacks quick release tubing, the separate bladder pocket with a generous opening helped simplify removal of the bladder.
The Nano 18 landed among the upper portion of the lineup in our comfort rankings, coming equipped with nicely padded shoulder straps and a back panel that hugged our body when fully loaded. This cushioning design is very similar to what we found on the Osprey Skarab 18.
The drawback to the cushy support provided by the Nano is that the breathability of the back panel is lacking. 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 waist belt consists of simple webbing straps, which weren't as comfortable under heavier loads as models with more substantial hip padding, like the like the Hydro Flask Journey Series 10L or the Editors' Choice Award winner Platypus Duthie A.M. 10. Since both those models have list prices double that of the Gregory Nano, we think that might be a fair tradeoff if you're looking to save some money.
While the padded back panel and shoulder straps were quite comfortable, there isn't much ventilation, and the waist belt isn't very supportive.
With 18 liters of storage space, the Nano 18 H2O ties with two other models as the largest pack with tested in this category. Of these three 18-liter models we tested, the Nano had 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 balanced 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 we found on our top-rated Osprey Syncro 12, our Editors' Choice Platypus Duthie A.M. 10, or for a lumbar version, our Top Pick Osprey Seral. 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.
At a measured 1 lb 9.5 oz, the Nano 18 H20 lands in the middle of our test packs when it comes to weight, but ties with the Osprey Skarab 18 as the lightest full backpacks in this category. While there are certainly some lighter offerings in the lineup, like our lumbar style packs or the lightweight CamelBak Rogue and svelte Camelbak Classic, 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 the insulated Hydro Flask Journey Series 10L or have heftier frames like the Deuter Compact EXP 12, those features certainly come at a weight premium. For a great balance performance and weight, the Gregory Nano is tough to beat.
Our Best Buy Award winner on the move.
Ease of Cleaning
As you'd likely imagine, with a smaller circular opening, the 3D Hydro bladder on the Nano 18 H2O was 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 other models, like the Deuter and Platypus 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. While not optimal for easy cleaning, it's certainly possible to get the job done.
The Quick Dry Hanger is a nice touch to help empty and dry out the bladder.
The Nano 18 H20 can be your go-to hydration pack for all-day adventures where a little extra storage is needed and a great choice if you want one pack that can double as a gym bag, an all-around daypack, or a carry-on for your next weekend flight. Though lacking some more luxurious features found on some higher-end models, this pack can take you anywhere you want to go.
The Nano 18 is capable of keeping up on your next adventure.
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, at a $70 list price, you're paying half of the list 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 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.