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Platypus DuoLock SoftBottle Review

This bottle combines a collapsible design with a spout for convenient, easy drinking
Platypus DuoLock SoftBottle
Credit: Platypus
Top Pick Award
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Price:  $15 List | Check Price at Backcountry
Compare prices at 3 resellers
Pros:  Useful carabiner attachment, well-designed lid, lightweight, very collapsible
Cons:  Tips easily, hard to clean
Manufacturer:   Platypus
By Jane Jackson ⋅ Senior Review Editor  ⋅  Mar 30, 2022
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55
OVERALL
SCORE


RANKED
#18 of 21
  • Ease of Use - 40% 5.0
  • Durability - 25% 3.0
  • Weight - 20% 10.0
  • Taste - 15% 5.0

Our Verdict

We have explored many iterations of the collapsible bottle over the years. We have found that it is surprisingly hard to make a new, yet still effective, bottle that is lightweight and compact. Yet it seems that Platypus has done just that with the Platypus DuoLock SoftBottle. This bottle is super lightweight, easy to carry, and has a revolutionary lid design that changed our opinion on collapsible bottles in general. The Duolock also has a carabiner attachment point that we found very useful for climbing, as it can be attached to your harness. There are many pros to this new design from Platypus, and we are happy to give the bottle the Top Pick for Collapsible Award this year. This bottle is best used for hydrating in backcountry settings — you can even fold it up and fit it in your back pocket, making it the most portable of the water bottles we tested. The carabiner clip-in point adds to its versatility in the wilderness.

Pro tip — On extended backcountry trips, we like coupling the DuoLock with a Nalgene.

Editor's Note: This product review was updated on March 25, 2022, to share more product recommendations for specific uses.

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Pros Useful carabiner attachment, well-designed lid, lightweight, very collapsibleSimple design, inexpensive, lightweightLight, durable, resists flavors, simple design, wide mouth makes for easy fillingAffordable, insulates well, has interchangeable lids, easily portableLightweight, collapsible, simple design
Cons Tips easily, hard to cleanMade of plastic, doesn't fit in all cupholdersDiameter too big for cup holders, wide mouth makes it difficult to drink from when walking or drivingPaint chipping after a few months of use, flip cap seemed to lack securityNot very durable, difficult to clean, retains flavors
Bottom Line This bottle combines a collapsible design with a spout for convenient, easy drinkingThis bottle is recommended because it is simple, lightweight, durable and has a solid feature setA tried and tested classic, this model is versatile and reasonably pricedThis is one of our favorite bottles because it's easy to use, just the right size, lightweight and inexpensiveWith its lightweight design and packability, this is one of the best collapsible bottles out there
Rating Categories Platypus DuoLock So... CamelBak Eddy+ Trit... Nalgene Wide-Mouth Simple Modern Summit Platypus SoftBottle
Ease of Use (40%)
5.0
8.0
8.0
7.0
3.0
Durability (25%)
3.0
8.0
7.0
8.0
3.0
Weight (20%)
10.0
8.0
8.0
4.0
10.0
Taste (15%)
5.0
7.0
7.0
8.0
4.0
Specs Platypus DuoLock So... CamelBak Eddy+ Trit... Nalgene Wide-Mouth Simple Modern Summit Platypus SoftBottle
Body Material Nylon / polyetholyene BPA-free plastic Eastman Tritan co-polyester 18/8 stainless steel Polyethylene
Empty Weight 1.6 oz 7.1 oz 6.4 oz 15.7 oz 1.2 oz
Volume 34 oz 32 oz 34 oz 32 oz 34 oz
Bottle Weight per Fluid oz Capacity 0.05 oz 0.22 oz 0.19 oz 0.5 oz 0.04 oz
Mouth Diameter .75 in 2.3 in 2.5 in 2.25 in 1 in
Base Diameter 6 in 3.8 in 3.25 in 3.5 in 6 in
Height 11 in 9.25 in 8.25 in 9 in 13 in
Body Type Collapsible Hard-sided/traditional Hard-sided/traditional Hard-sided/traditional Collapsible
Free of Materials BPA-free BPA, BPS, BPF free BPA, BPS and Phthalate Free BPA-free BPA-free
Cap/Lid Type Duo-Lock flip cap Screw cap, flip top Loop-top screw cap Screw Cap, flip top Closure cap
Volume Options .75 L, 1L 14 oz, 25 oz, 32 oz 16 oz, 48 oz 14 oz, 18 oz, 22 oz, 32 oz, 40 oz, 64 oz, 84 oz 0.5 Ltr, Push-Pull cap

Our Analysis and Test Results

Much like its predecessor, the Platypus SoftBottle, the DuoLock is light, portable, and ideal for hiking in the backcountry or climbing up a multi-pitch route. The bottle is easy to fill, and the new lid makes staying hydrated a breeze. The downsides to this bottle are also similar to the SoftBottle. It is difficult to drink from at times since its flexible body is a bit floppy. Also, the bottle is one of the more difficult ones to clean due to its narrow mouth and some nooks and crannies that are hard to reach.

Performance Comparison


Platypus DuoLock SoftBottle water bottle - this bottle is best used on hikes or stuffed into a climbing pack...
This bottle is best used on hikes or stuffed into a climbing pack because of its weight and portability.
Credit: Jane Jackson

Ease of Use


The DuoLock has a collapsible plastic body and screw-on cap. What sets the DuoLock apart from previous Platypus models is its newly designed two-part lid. The lid can be removed for filling, but it also has a flip cap that makes for easy drinking. We found that we spilled water on ourselves a lot less. Some bottles have similar lid designs, but the DuoLock's actually makes sense with the overall design of the bottle. Another plus for this contender is that it forms to the space available in your pack for easy stowing. The flexible body is also helpful when filling the bottle in shallow streams in the backcountry. It is leak-proof beyond any doubt, and easily rolls up and fits into your pocket when empty.


On the downside, drinking from this collapsible bottle requires a learned skill, and usually requires two hands. Its soft flexibility makes it flop around when trying to grab a drink, which will lead to spills if you're not careful. This is not a one-handed drinking bottle, but if you're using this bottle, hopefully, you are in the backcountry or on some kind of adventure where you will have time to use both hands to hydrate yourself. The DuoLock also had a tendency to fall over, which is a problem for all lightweight, collapsible bottles we have tested.

Platypus DuoLock SoftBottle water bottle - when full, the platypus duolock stands up on its own, even on uneven...
When full, the Platypus DuoLock stands up on its own, even on uneven surfaces!
Credit: Jane Jackson

This contender also has one of the smallest mouths of all bottles we tested, making it hard to fill up from faucets with large or powerful water streams. Its narrow mouth also makes it quite challenging to clean. As we mentioned with the Platypus SoftBottle, the DuoLock has a small mouth that will require a different bottle for purification with some filters or a Steri-Pen. This is a reminder for those who are planning on taking this bottle into the backcountry. Liquid and tablet water treatments will work fine in this bottle, though, as would a Sawyer Mini water filter.

Platypus DuoLock SoftBottle water bottle - the duolock combines a secure lid with a useful and effective spout...
The DuoLock combines a secure lid with a useful and effective spout, making it our new favorite over the older, simpler Platypus SoftBottle.
Credit: Jane Jackson

Durability


The DuoLock can easily handle drops and falls onto hard surfaces. It breezed through our drop tests, barely suffering a scratch (a minute scratch on the cap was all). That said, you can't expect a collapsible bottle to last forever. It held up fine in our three-month review, but in personal experience, we haven't had a collapsible bottle that held up much more than a year. For this reason, we recommend always having another water container as a backup. If you fold the bottle up for storage frequently, the bottle will wear more quickly along the fold lines and could risk having a hole form on the seam.


Weight


It is in this category that the bottle really shines.

Platypus DuoLock SoftBottle water bottle - here, the compact size of the duolock is shown on the left, while...
Here, the compact size of the DuoLock is shown on the left, while the Platypus Meta on the right does not collapse nearly as well.
Credit: Jane Jackson

The DuoLock is one of the lightest bottles in this review, weighing in at 1.6 ounces. That works out to being only five-hundredths of an ounce per fluid ounce. That means that the weight in your pack is not your bottle, but just the water you need to keep going on the trail. The other collapsible bottles scored right in line with the DuoLock in this metric.


Taste


Drinking from this water bottle tasted fine at first. However, if you store your water in this bottle for over 24 hours, expect it to have a plastic-y taste. It also retained the taste of the flavored sports drink in subsequent fills. Much like the LifeStraw Go, we recommend filling the PlatyPus DuoLock with water only. This is the downside of the bottle being plastic, and collapsible as the flexible plastic seems to impart its flavor on the liquid more than solid plastic bottles.


Unfortunately, the DuoLock had some issues with soapy flavor retention. After an issue with lingering soapy flavor, we were able to return the bottle to a neutral taste after filling it with baking soda and vinegar for 12 hours and rinsing. The best way to use these malleable plastic bottles is to simply use them for drinking water and try not to get other flavors imparted into their plastic walls.

Platypus DuoLock SoftBottle water bottle - the carabiner on the duolock is substantial enough to clip onto a...
The carabiner on the DuoLock is substantial enough to clip onto a harness when rock climbing.
Credit: Jane Jackson

Should You Buy the Platypus DuoLock SoftBottle?


The Platypus DuoLock is an ideal bottle for backpacking and traveling — not so much as an everyday urban bottle. Its lightweight design, clever lid, and incorporated carabiner clip make this bottle a great option for those counting ounces for their next adventure. The flexible body can collapse into the size of a plastic bag and stows away easily. It is easy to fill this bottle from a stream, but the narrow mouth makes it hard to filter water. It also requires two hands for drinking, which means it is not the ideal bottle for road trips. Overall, the DuoLock is a great bottle and our Top Pick for collapsible bottles.

What Other Water Bottles Should You Consider?


If you want a non-plastic collapsible bottle, the Hydrapak Stow is a lightweight silicone option that folds up small and is ideal for uses like stashing into your jacket for sips of water on the ski hill. Our long-standing favorite all-purpose backcountry bottle is the Nalgene Wide-Mouth. If you just need an around-town daily driver, check out the Yeti Rambler 26, which is our favorite overall due to its ease of use and durability.

Platypus DuoLock SoftBottle water bottle - the duolock gets its name from this lid design. instead of screwing...
The DuoLock gets its name from this lid design. Instead of screwing the lid down, it locks into place, eliminating leakage.
Credit: Jane Jackson

Jane Jackson
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