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Nathan
Insulated Bite Top 18oz Soft Flask

4.666666666666667 out of 5 stars
12 Reviews

Out of Stock

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Insulated Soft Flask with Bite Top

When you're running on warm summer days, it's nice to have a cold, refreshing drink. With the Nathan Insulated Soft Flask with Bite Top, you'll have 18oz of cool refreshment as you run. Its insulated design keeps fluids cooler 38% longer than non-insulated soft flasks so you can expect a refreshing drink even when you're several miles deep. And conveniently, the flask is compatible with all Nathan hydration vests.


Details

  • Insulated soft flask to keep liquids cool while you run
  • 18oz provides you with plenty of on-trail refreshment
  • Bite valve design prevents your liquids from escaping
  • Insulated design keeps the contents cooler for longer
  • Flask is compatible with all Nathan hydration vests
  • Item #NAT004O
Volume
18oz
Lid
bite
Manufacturer Warranty
limited

Overall Rating

4.5 based on 12 ratings

Review Summary

1 Stars - 0 reviews
2 Stars - 0 reviews
3 Stars - 2 reviews
4 Stars - 0 reviews
5 Stars - 10 reviews

What do you think about this product?

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5 out of 5 stars

June 15, 2023

Works Great

Easy to drink from and fits perfectly in my vest. Put a few ice cubes in it and it stayed cool my whole run. Used it for my electrolytes so I don’t have to bother washing it all out of the bladder.

Katie
nathansports.com

Originally reviewed on nathansports.com

5 out of 5 stars

April 8, 2023

Thankful for Insulation

[This review was collected as part of a promotion.] I love this collapsible flask because it’s insulated. Water gets hot quickly in the heat but this thoughtful insulation keeps my water cooler longer which helps a ton on long runs.

Ultraorbustbrandi
nathansports.com

Originally reviewed on nathansports.com

5 out of 5 stars

March 7, 2023

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.

user image
Ultraorbustbrandi
nathansports.com

Originally reviewed on nathansports.com

5 out of 5 stars

January 17, 2023

Perfect Fir

Excellent. It perfectly fit in my Nathan Hydration vest.

Nye Gree
nathansports.com

Originally reviewed on nathansports.com

5 out of 5 stars

September 26, 2022

Works great!

Love it! Easy to drink from and comfortable to hold.

MegRuns2
nathansports.com

Originally reviewed on nathansports.com

5 out of 5 stars

October 16, 2021

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!

Jen P.
nathansports.com

Originally reviewed on nathansports.com

5 out of 5 stars

August 3, 2021

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!

Scott M
nathansports.com

Originally reviewed on nathansports.com

5 out of 5 stars

July 29, 2021

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.

The Luxi
nathansports.com

Originally reviewed on nathansports.com

5 out of 5 stars

December 26, 2020

Soft Touch

Conveniently holds an extra 18oz on my long runs. My water stays cold and it is easy to hold. Collapses as it empties. Making it convenient to store away.

Illizibith
nathansports.com

Originally reviewed on nathansports.com

3 out of 5 stars

July 20, 2020

Wasn’t as insulated as i would have hoped

This was great for my hiking knapsack but I did not feel it kept my water colder than any other bottle.

Candice
nathansports.com

Originally reviewed on nathansports.com