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Hydro Flask 40 Oz Wide Flex Cap Black

  • Based on 27,509 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon

Arrives Aug 30 – Sep 5
Order within 9 hours and 34 minutes
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Style: 40 Oz


Color: Black


Features

  • 40 OZ WATER BOTTLE: The stainless steel insulated reusable water bottle keeps drinks cold for 24 hours, and hot up to 12. This Hydro Flask bottle is dishwasher safe and easy to clean.
  • 24 HOURS COLD. 12 HOURS HOT: Double-wall vacuum insulation keeps drinks hot or cold for hours. The insulated bottle keeps beverages cold for 24 hours and hot up to 12. The TempShield insulation keeps the water bottle cool to the touch.
  • LEAKPROOF: Say goodbye to leaky water bottles. The Hydro Flask Flex Cap is leakproof when closed. Toss it into your bag without worry.
  • PURE TASTE: Durable pro-grade stainless steel ensures pure taste and no leftover flavor transfer. So, today's water won't have any taste of yesterday's iced tea.
  • DISHWASHER SAFE: Easy to use and easy to clean, just toss the lid and bottles into the dishwasher. Designed to keep bright color, being dishwasher safe means your favorite Hydro Flask is always at-the-ready.

Description

Stainless steel, insulated, refillable, reusable—our wide-mouth water bottle is the flask to grab to keep cold drinks cold and hot ones hot. The large opening makes it easy to add ice—and get yourself a bigger gulp.

Brand: Hydro Flask


Capacity: 40 Fluid Ounces


Color: Black


Recommended Uses For Product: Water


Special Feature: Cold 24 Hours, Leakproof, Dishwasher Safe, Hot 12 Hours


Brand: Hydro Flask


Capacity: 40 Fluid Ounces


Color: Black


Recommended Uses For Product: Water


Special Feature: Cold 24 Hours, Leakproof, Dishwasher Safe, Hot 12 Hours


Age Range (Description): Adult


Product Dimensions: 3.55"W x 12.7"H


Model Name: Wide Mouth Flex Cap Bottle


Item Weight: 0.09 Pounds


Theme: Solid


Material: STEEL


Number of Items: 1


Pattern: Bottle


Included Components: bottle, lid


Product Care Instructions: Hand Wash Only


Base Diameter: 3.6 Inches


Cap Type: Flex Cap


With Lid: Yes


Is Dishwasher Safe: Yes


Is Microwaveable: No


Is Oven Safe: No


UPC: 810007831770


Manufacturer: Hydro Flask


Number of Packs: 1


Item Weight: 1.48 ounces


Department: Unisex-Adult


Item model number: W40BTS001


Assembly required: No


Number of pieces: 1


Warranty Description: LIFETIME


Batteries required: No


Import: Imported


Frequently asked questions

The Hydro Flask Wide Mouth Bottle with Flex Cap is made from high-quality 18/8 pro-grade stainless steel. This type of steel is recognized for its strength and purity, ensuring the bottle does not give off any flavors to your drink.

The Hydro Flask Wide Mouth Bottle is available in various sizes, but the most popular are the 32oz and 40oz variations.

Yes, the Hydro Flask bottle comes with TempShield Insulation. This technology keeps liquids icy cold for up to 24 hours and hot drinks hot for up to 12 hours.

Yes, the Flex Cap is designed to be leak-proof, making the Hydro Flask bottle convenient for transport without worrying about spills.

Top Amazon Reviews

🚀 Abunda's Overview

This is our summary and key points to consider based on customer reviews.


The Hydroflask product reviews suggest mixed feelings among users. They appreciate the product's ability to keep beverages ice cold for long periods and its capacity to meet drinking needs. However, there are concerns about the quality of certain Hydroflask products, with users identifying possible counterfeit items, issues with denting and rusting, as well as missing features in recent models.

Pros

  • 👍 Keeps beverages ice cold for extended periods.
  • 👍 Good for everyday use.
  • 👍 Does not transfer weird taste to the beverage.
  • 👍 Available in different colors.
  • 👍 Easy to clean.

Cons

  • 👎 Some units displayed signs of rusting.
  • 👎 Suspected presence of counterfeit items.
  • 👎 Some received already dented items.
  • 👎 Questions about its durability due to easy denting.
  • 👎 Recent models missing features present in old models.

Should I Buy It?

While the Hydroflask offers solid benefits like temperature retention and everyday usability, significant inconsistencies relating to product quality have been raised. If choosing to purchase, ensure to do so from a reputable dealer to avoid counterfeits and pay close attention to product handling to mitigate the denting concern. If these considerations don't dissuade you, it may be worth a try.


  • Great Insulation, Perfect Size
Style: 32 Oz Color: Black
The Hydro Flask 32oz water bottle has quickly become my go-to for staying hydrated throughout the day. It hits the sweet spot in size — large enough to keep me hydrated for hours without being too bulky to carry around. Whether I’m at the gym, at work, or on a hike, it’s the perfect companion. The insulation is seriously impressive. My water stays ice-cold for literally the entire day — sometimes even into the next. I’ve also tested it with hot beverages during the winter, and it performs just as well. The double-wall vacuum insulation does exactly what it promises. Design-wise, it’s sleek and simple but still feels durable and high-quality. I opted for a matte finish and it not only looks great but also gives a nice grip. The wide mouth makes it easy to fill, clean, and add ice cubes, and the lid seals tight with zero leaks. I also love that it fits in most cup holders and backpack side pockets, despite the larger size. If you’re looking for a reliable, well-designed water bottle that keeps your drinks cold (or hot) for hours, the Hydro Flask 32oz is absolutely worth the investment. It keeps me drinking more water, and honestly, I kind of look forward to carrying it around. ... show more
Reviewed in the United States on May 21, 2025 by gonzogl

  • Great purchase - I bought another one!
Style: 32 Oz Color: Black
Nice big water bottle that holds a lot of water. I like that the top has such a wide opening to make it easy to clean. The lid seals securely and the bottle is very durable. The only thing to keep in mind is it won't fit in your car cup holder. But the lid is so secure that I can toss it in the seat next to me without any concerns. ... show more
Reviewed in the United States on July 5, 2025 by Amazon Customer

  • Beautiful and functional
Style: 32 Oz Color: Surf
So far it's great - nice color and beautiful design, very durable due to being metal, fatter than most other metal bottles so it doesn't fall over so much (could be even fatter like a Nalgene). It has developed a slight nasty smell but you don't notice it unless you're paying attention. The handle is probably unnecessary, it's easier to just hold the bottle usually. The main issue is that it's kinda heavy -- due to the whole microplastics thing I would have switched to a metal bottle much earlier if not for the weight, but I guess that might require new technology to solve. ... show more
Reviewed in the United States on June 10, 2025 by anonymous

  • OK Plus
Style: 40 Oz Color: Indigo
I didn't have the bottle for long time because it got lost. I liked it, mainly the big size and the holding. Not so easy to open it though. I think it will be good choice for family's outdoor activities. Overall works well.
Reviewed in the United States on July 7, 2025 by Dovale

  • Practically perfect flask
Style: 40 Oz Color: Indigo
Love it. I got this for my elderly father, upgrading it with the metal lid. It’s of a perfect size, and not at all heavy for him to carry around when full. It keeps its hot contents hot and cold contents cold. It’s a big improvement for his single walled flask which could not be used for hotter liquids. Even when wet the texture gives enough grip to prevent slipping. The wide mouth also makes it easier to get a brush inside and clean along the tapered portion. I have the 64oz, which is another wonderful product, but this one hits the mark in so many ways. ... show more
Reviewed in the United States on June 4, 2025 by Sameer Sheikh

  • Still Chiilin’ with my water bottle
Style: 32 Oz Color: Goji
I have been using this for quite some time. It easily keeps my drinks cool for 24+ hours. It doesn’t even melt for 18-24 hours depending how much I put in it. I use it every day and have been incredibly happy.
Reviewed in the United States on July 5, 2025 by Martin H Pomerantz

  • Worked great, only one little hiccup
Style: 20 Oz Color: Trillium
I bought this thermos to keep water hot for making bottles for my picky baby when we were traveling. It did a good job keeping the water warm enough for her for up to 8 hours. However, I had problems with the rubber inner seal falling out. This happened when TSA would check the thermos and it was a big inconvenience. I imagine this happens when you put hot water in it but still, it’s a drawback. All in all it worked well for me and it’s a beautiful color. ... show more
Reviewed in the United States on June 11, 2025 by Myriah Smith

  • Great quality!
Style: 20 Oz Color: Surf
This is a GREAT water bottle. With the wide mouth, it is easy to fill with ice. It is not as huge as some bottles, which was one of the reasons that I chose it; it is not bulky, it's easy to hold, and it fits in our car's cup holders. A bit pricey, but this is a quality item. Used it today and it kept my ice water COLD. Now my husband wants his own! My research paid off. Go for it! ... show more
Reviewed in the United States on June 16, 2025 by Linda Fitz

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