21 oz Standard Mouth
Your perfect travel companion.
Keep life moving with our 21 oz bottle and Standard Flex Cap. It stashes easily into a small shoulder bag, your pack’s side pocket, or your car cup holder, and holds enough ice cold goodness to keep you going for hours without weighing you down. No wonder it's one of our bestselling water bottles.

TempShield™
Our unique double wall vacuum insulation protects temperature for hours. Cold drinks stay icy cold and hot drinks stay piping hot so you can stay refreshed for any adventure.


Pro-Grade Stainless Steel
Made with 18/8 pro-grade stainless steel to ensure pure taste and no flavor transfer - and the durable construction stands up for whatever life brings.
Proprietary Powder Coat
Our proprietary powder coat means an easy-grip, sweat-free, and extra-durable bottle that you can take anywhere.

Product Benefits
- Versatile, middle-of-the-road size
- TempShield™ insulation eliminates condensation and keeps beverages cold up to 24 hours and hot up to 12 hours
- Durable 18/8 Pro-Grade Stainless Steel construction
- BPA-Free and Phthalate-Free
- Compatible with Standard Mouth Insulated Sport Cap
- Lifetime Warranty
Size & Dimensions
21 oz | |
---|---|
Volume | 621 mL |
Mouth Diameter | 1.91" |
Diameter | 2.87" |
Height | 9.4" |
Weight | 11.3 oz |
Lifetime Warranty
We stand behind our products.
Hydro Flask guarantees this product with a limited lifetime warranty against manufacturer defects.
Hydro Flask supports non-profit organizations focused on building, maintaining, restoring, and providing better access to parks. Since 2017, we have been doing just that:
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92 Non-profits supported non-profits.
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$1.5 million Dollars donated donated.
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26,043 Bottles donated bottles.
Do they float? I'm looking for something with a closed lid to use on my kayak and with the possibility of flipping the kayak I would like to make sure I will be able to locate the flask if that were ever to happen.
Will this size fit in a standard cupholder?
I bought my Hydro Flask at Dick’s Sporting Goods will I still be offered the lifetime warranty?
Are any of the water bottles dishwasher safe?
I am getting a metallic taste in my water from the 21 oz flask. I’m surprised as it has 18/10 stainless steel. Is there anything that would get rid of this?
Can I use the lid with the straw for coffee in the standard mouth 24 oz bottle
Where is this bottle manufactured?
Is there a cap available for purchase that would allow me to use my standard mouth Hydro Flask 21oz with hot drinks? I purchased 2 hoping to use one for hot and the other for cold. However I have not been able to use hot drinks due to the cap. Frustrated
Hydro Flask supports non-profit organizations focused on building, maintaining, restoring, and providing better access to parks. Since 2017, we have been doing just that:
-
92 Non-profits supported non-profits.
-
$1.5 million Dollars donated donated.
-
26,043 Bottles donated bottles.