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Hydro Flask

Hydro Flask 21 Oz Standard Flex Cap Stone

  • Based on 16,676 reviews
Condition: New
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$34.95 Why this price?

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This item is eligible for return within 30 days of receipt

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Availability: In Stock.
Fulfilled by Amazon
Arrives Thursday, Jul 10
Order within 14 hours and 53 minutes
Available payment plans shown during checkout

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Style: 21 Oz


Color: Stone


Features

  • Stainless steel
  • Imported
  • 24 hours cold, 12 hours hot
  • TempShield double-wall vacuum insulation
  • Leakproof when closed
  • Pure taste, no flavor transfer
  • Durable stainless steel
  • BPA-Free
  • Dishwasher safe
  • Not for use on a stove, in a microwave or freezer
  • Keep hot liquids out of the reach of children
  • water bottle, leakproof, insulated, 24 hours cold, 12 hours hot, dishwasher safe, 21 oz, cupholder compatible

Description

Stainless steel, cupholder compatible, fits anywhere—the compact, reusable, refillable Standard Mouth insulated water bottle keeps cold drinks cold for 24 hours, hot drinks hot for up to 12 hours, and holds enough hydration for quick adventures.

Brand: Hydro Flask


Capacity: 21 Fluid Ounces


Color: Stone


Recommended Uses For Product: Water


Special Feature: TempShield™ insulation, Proprietary Powder Coat


Brand: Hydro Flask


Capacity: 21 Fluid Ounces


Color: Stone


Recommended Uses For Product: Water


Special Feature: TempShield™ insulation, Proprietary Powder Coat


Age Range (Description): Adult


Product Dimensions: 1.12"W x 4.37"H


Model Name: Standard Mouth Flex Cap Bottle


Item Weight: 23.68 g


Theme: Sport


Material: Stainless Steel


Number of Items: 1


Pattern: Bottle


Included Components: bottle, lid


Product Care Instructions: Dishwasher safe


Base Diameter: 2.8 Inches


Cap Type: Flex Cap


With Lid: Yes


Is Dishwasher Safe: Yes


Is Microwaveable: No


Is Oven Safe: No


UPC: 810007834818


Manufacturer: Hydro Flask


Global Trade Identification Number: 18


Item Weight: 0.835 ounces


Department: unisex-adult


Country of Origin: China


Item model number: S21SX010


Volume: 621 Milliliters


Fabric Type: Stainless steel


Refill: vacuum


Tick-repellent material: Stainless steel


Assembly required: No


Number of pieces: 1


Warranty Description: LIFETIME


Batteries required: No


Import: Imported


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Jul 10

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
  • PayTomorrow Financing
  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

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Top Amazon Reviews

    • Love it.
After I lost a generic souvenir bottle my mom got me at school, which I wish I could find out the name of so I can rant about it because it would spill no matter how much you tipped it, which resulted in multiple large spills in the few weeks I used it, I ordered this because I knew the brand had a reputation for quality and the size was exactly what I needed, and it did not disappoint. It fits perfectly in the pocket of a bag and it hasn't leaked once. Very easy to open, although it felt a bit tight when I first got it, the color looks great, and, while it's a bit expensive, I think you still get your money's worth from this bottle. ... show more
Reviewed in the United States on June 24, 2025 by Devin Quay
    • Great water bottle for a day out
I have many pieces of Hydro Flask now. They are well made, keep water cold all day, and reasonably priced. I got this one because the opening is large enough for ice cubes and still easy to drink out of without spilling. I have the 21 Oz which fits nicely in my car cup holder. It is sleek looking and the little handle on top is handy. ... show more
Reviewed in the United States on June 14, 2025 by Sue K
    • Diseño minimalista , lijera
The media could not be loaded. Recientemente adquirí la Hydro Flask de 21 oz. en color Verde Aloe, y estoy realmente satisfecho con mi compra. Lo primero que me atrajo fue su diseño minimalista y elegante. Pero más allá de la estética, esta botella es práctica. Sella herméticamente, lo que significa que no tengo que preocuparme por fugas o goteos. Una de las razones clave por las que elegí este modelo es el tamaño de su abertura. Es lo suficientemente grande como para facilitar una limpieza profunda y sin complicaciones. Además, el diseño de la boquilla permite beber fácilmente sin derrames. Me alegra decir que esta Hydro Flask cabe perfectamente en el bolsillo lateral de mi mochila sin ningún problema. Un pequeño detalle a considerar es que el color real "Verde Aloe" es un poco más claro de lo que aparece en las fotos, pero esto no disminuye mi satisfacción con el producto. ... show more
Reviewed in the United States on June 29, 2025 by Maria Doris Henao Marin
    • No weird smell from the bottle while drinking
It keeps my drink at the right temperature really well. I also don’t notice any strange smells when drinking, which is a big plus compared to other products I’ve used before.
Reviewed in the United States on June 17, 2025 by Patrick Smith
    • Keeps my drink cold
I really enjoy this item. It keeps my drinks cold for a long time, even on hot days.
Reviewed in the United States on June 21, 2025 by Jeff Enriquez
    • Excellant but pricey at $27 but not too happy for $34.
Edited: Very nice water bottle! (for $27). Hydro Flask bottles are beautiful, minimalist design but it's a little hard to swallow, even more so with its big brother the “wide mouth flex chug”. I loved both but up to $34 and $42 respectively is cra cra. The hands down winner is the Farsea brand 24 oz with paracord handle, integrated cap handle and removable silicone. I picked up the beautiful Farsea with dual caps for $22 it's a water bottle! I'm on the Zep shot, happily losing weight here, but lets us not go too crazy....it's a water bottle. I picked up a nice Wontego paracord shoulder strap as a nice addition that none of them include for $11 so maybe I went a little crazy, but I’m happy with end product. :) ... show more
Reviewed in the United States on June 15, 2025 by VinceP
    • Blue Hydro Flask
Got beat up a bit but still stayed strong.
Reviewed in the United States on June 27, 2025 by Daphne
    • The BEST!
Best water bottle! Keeps liquid cool for hours.
Reviewed in the United States on June 22, 2025 by L. Scott

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