Thermos Guardian Stainless Hydration Review
Cons: Leaks, flip-cap is challenging to operate, lacks durability
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Thermos Guardian Stainless Hydration
|Price||$25 List||$8.73 at REI|
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|$16.99 at Amazon|
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|$18.99 at Amazon||$10.00 List|
|Pros||Affordable, easy to clean||Light, durable, resists flavors, simple design, wide mouth makes for easy filling||Lightweight, easy for one-handed drinking, re-designed sport cap is effective, durable, good color options||Affordable, insulates well, has interchangeable lids, portable||Inexpensive, passed our drop tests, easy to carry, easy to drink from, ergonomic design|
|Cons||Leaks, flip-cap is challenging to operate, lacks durability||Diameter too big for cup holders, wide mouth makes it difficult to drink from when walking or driving||Sport cap not as secure as a screw cap, carrying handle is small||Paint chipping after a few months of use, flip cap seemed to lack security||Narrow mouth makes it hard to clean by hand, heavy, inherently less durable than steel competition|
|Bottom Line||A vacuum insulated bottle with a lackluster feature set||A tried and tested classic, this model is versatile and reasonably priced||It is hard for us to find anything bad to say about this bottle, as it's simple, easy to use, and reasonably priced||This is one of our top ranking bottles because it's easy to use, just the right size, lightweight and inexpensive||This affordable bottle's no-nonsense, ergonomic design wins us over for the top glass option of all we tested|
|Rating Categories||Thermos Guardian St...||Nalgene Wide-Mouth||Klean Kanteen Classic||Simple Modern Summit||Ello Pure 20|
|Ease Of Use (40%)|
|Specs||Thermos Guardian St...||Nalgene Wide-Mouth||Klean Kanteen Classic||Simple Modern Summit||Ello Pure 20|
|Body Material||18/8 stainless steel||Eastman Tritan co-polyester||18/8 stainless steel||18/8 stainless steel||Glass/ BPA-free silicone|
|Empty weight (oz)||12.7 oz||6.4 oz||7.4 oz||12.4 oz||18.5 oz|
|Volume (oz)||24 oz||34 oz||27 oz||22 oz||20 oz|
|Bottle weight (oz) per fluid oz capacity||0.53 oz||0.19 oz||0.27 oz||0.56 oz||0.93 oz|
|Mouth diameter||2 in||2.5 in||1.75 in||2.25 in||1.75 in|
|Base diameter||2.5 in||3.25 in||2.75 in||3 in||3 in|
|Height||10 in||8.25 in||11 in||9.5 in||10.75 in|
|Free of Materials||BPA, BPS and Phthalate Free||BPA, BPS and Phthalate Free||BPA-free||BPA-free||BPA-free|
|Cap/Lid Type||Screw top with flip cap||Loop-top screw cap||Sport cap wih spout||Screw Cap||Screwtop|
|Volume Options||24oz, 40 oz||16 oz, 48 oz||18 oz, 40 oz, 64 oz, loop cap/sports cap, wide mouth||14 oz, 18 oz, 22 oz, 32 oz, 40 oz||20 oz|
|Warranty||None||Lifetime Guarantee for normal use||Lifetime Warranty||Limited Warranty||Lifetime warranty|
Our Analysis and Test Results
The flip cap is becoming more and more prevalent in water bottle design across the board. Stainless steel, plastic, and glass bottles are now often coming with a one-handed button-operated lid. The Thermos Guardian is one such bottle, but unfortunately our least favorite iteration of this design we've tested. The Guardian was not easy to operate and its carrying handle felt bulky and poorly shaped. It did insulate fairly well and didn't impart flavors too much.
Ease of Use
This metic is really where the Thermos Guardian falls short. The lid has a push button, a locking mechanism, and a carrying handle, but all of these features felt like they were made from cheap materials that didn't work very well. The lock worked but felt gimmicky. The push-button was sticky and often required a second push to actually open. Finally, the carrying handle doesn't fold flush against the bottle, so it sticks out at a 90-degree angle when not in use, which bothered our testers. On the plus side, it is easy to fill and clean, as its wide mouth accommodates a bottle brush easily. The lid, though complex and clunky, also cleans fairly easily due to its wide spout.
Overall, this stainless steel option did well in our durability tests. When dropped, the bottle got a few small scuffs and a small indent on the bottom, but beyond that was unscathed. This is typical for a stainless steel, insulated bottle, but we were pleased nonetheless.
When it came to our leak test, though, the Thermos Guardian was a little less impressive. When shaken, even with only water inside, the bottle leaked a few drops out of the flip cap. When left resting on its side filled with colored water, a few drops leaked out onto the paper towel after a few hours. Again, this reaffirmed our lack of confidence in the overall lid design on this one.
In comparison to its stainless steel peers, the Thermos Guardian is impressive when it comes to weight. Though its capacity is only 24 ounces, the bottle weighs in at 12.7 ounces, giving it a weight-to-volume ratio of 0.53 ounces. This is on the lighter end of the spectrum in the world of vacuum-insulated bottles.
When we conducted our taste test on the Guardian we were impressed by its easy-to-clean design and its ability to shed flavors. If this bottle has a strong suit, this testing metric would certainly be it. After filling it with drink mix and then washing it with a bottle brush and a tiny bit of soapy water, the Guardian was more or less returned to its original state. Additionally, there were no plastic-y flavors when we took it out of the box initially, adding to its high score in this metric.
This is a very affordable bottle, especially compared to its vacuum-insulated, stainless steel counterparts. The Guardian is on the cheaper side of most of the bottles we tested and it shows. We hate to say it, but this bottle doesn't seem like it was built to last. The flip-cap started to get sticky after only a few days of use and the locking mechanism was prone to get stuck as well.
Though it's affordable, the Thermos Guardian was not our favorite bottle in the line-up. Its feature set left a lot to be desired — the buttons were clunky and the carrying handle was ill-sized and bulky. It is easy to drink from the spout, but the button to open the flip cap didn't work very well. We think most folks will be better served looking for a different bottle with fewer gimmicks and more simple functionality.
— Jane Jackson