Nathan Insulated Soft Flask - 18 fl. oz.
Designed to keep you hydrated on the move, the Nathan insulated soft flask provides big-time insulation for big-time thirst, keeping your H2O cool for mile after mile.
- 18 fl. oz. BPA-free soft flask with locking cap and bite-valve design keeps liquids from escaping while you run
- Support spine creates a superior hand feel and support for the flask as the water level decreases in the bottle
- Insulated design keeps fluids cooler 38% longer than non-insulated soft flasks
- Compatible with all Nathan hydration vests (not included)
Imported.
View all Nathan Running Water Bottles| Best Use | Running |
|---|---|
| Liquid Capacity (L) | 0.5 liters |
| Liquid Capacity (fl. oz.) | 18 fluid ounces |
| Dimensions | Unavailable |
| Water Bottle Material | Plastic |
| Material(s) | Soft plastic |
| BPA Free | Yes |
| Insulated | Yes |
| Bottle Opening | Medium |
| Cap Type | Squeeze |
| Collapsible | Yes |
| Weight | Unavailable |
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Excellent idea, not perfect
I was so excited to see this product, it's been something I've been hoping for. The insulation keeps ice water cold fairly well - much better than nothing, but not as good as an insulated hard bottle (to be expected). The majority of the bottle doesn't form any condensation even with ice water inside. Unfortunately (and my reason for 4 stars instead of 5) the top area of the bottle, and a black strip along the body isn't insulated and condensation does form there.
Never got to use it before it broke
I put this in the dishwasher, top rack, as it says you can do. After washing it for my first use, I noticed the top looked different. The valve came out in the dishwasher and it’s gone gone. The bottle is useless now. Total waste of money.
Hello and thank you for your review of our 18oz Insulated Soft Flask. I am sorry to see that this has occurred with your cap. Please contact out customer service department at (800) 233-6956 or cs@unitedspb.com and we will assist you with getting a replacement.
Love that it’s insulated!
[This review was collected as part of a promotion.] Love this flask. I ordered extras to keep in my drop box and switch out for races.
I ended up returning it
I previously wrote a 4 star review titled 'Excellent idea, not perfect'. However, I ended up returning this product because the taste of the water after being in the flask for more than an hour was not to my liking. If the flask kept drinks cooler for longer I might be willing to deal with the taste, but being that the drink got warm fairly fast, and the water tasted horrid, I couldn't justify keeping this item. What a shame, I hope Nathan and others continue to innovate here, as the idea is solid.
Superbly designed!
Superbly designed! I use two of these bottles with the Nathan VaporSwift 4L Hydration Vest. They fit perfectly in the front pockets and I can sip from them without removing them from the vest while running. There is absolutely no sloshing as the bottle shrinks as you drink, no leaking, a proper level of flow when you do drink and when they are fully loaded on the front of the vest they do not bounce as the pocket comes up just over the top edge of bottle leaving the bottle nipple exposed. I label one for water and one for electrolytes. These help me run safely on the hottest Southern California trails. The lids can be a little tricky to screw on but I see that as a fair trade off for never seeing a leak. Well done Nathan!
So far so good!
I took two of these on a 3-hour run in 23 degrees Fahrenheit. Plain water did not freeze at all, not even at the aperture! They fit well in my Ultimate Direction ultra vesta 6.0 hydration vest. I also like how the opening is designed: just bite and drink - nothing to snap open or closed, so no need to take off your mittens. I'm excited to see if they can keep water (or at least Gatorade) from freezing at zero or sub-zero temps!
stylish and practical.
The flask has just the right level of rigidity to feel comfortable without being wobbly. The bite top is quality and enables suction without air being sucked in avoiding the flask to inflate with air as you drink from it. I use it for fresh juice. It needs a good clean and an odor of the juice remains afterwards but doesn't small foul. I run in very hot climate and the content did heat up fairly within about half an hour. But as I am in such a hot climate I am not in the best position to rate the insulation for normal conditions.
Maybe BPA free but the STINK spoils the DRINK!
Such a plus to have a soft water bottle, BPA free and....it stops there. Rated as SMELL free, yet I could hardly tolerate the STINK my pure NZ water acquired upon use. Not even worthy of a star with such a material smell problem...and I can't return it cause I missed the return deadline due to the pandemic...waste of $.
Great design and fit
Love this for my running vest. Not a fan of the straw systems because I can always taste the plastic no matter the manufacture says. I like the top on this and can just squeeze the flask while running to get a quick drink! It fits in both of my vests and holds just the right amount of water I need for 13.1 on the road or trails!
Soft side water bottles are great
Soft side water bottles are great! This Nathan item is without handhold. I love that. I can side the water bottle in my race pack and go hands free. This item is only at REI. On Nathan website, it come with a strap to hand hold the bottle. Thank REI for getting me exactly what I want.