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Which Iron Flask is best?

Not to be confused with traditional flasks, the Iron Flask brand includes water bottles, mugs, food jars, and tumblers made of some of the best stainless steel materials available. By contrast, a traditional flask is simply a slim and small bottle, typically made of metal or glass and used to store small amounts of drinks. Iron Flask has revolutionized how flasks and other convenient-sized bottles are made with various drink containers available in different colors and sizes. If you’re looking for a stylish water bottle that will keep drinks warm or cold, the Iron Flask 32 oz Sports Water Bottle is the top choice. 

What to know before you buy an Iron Flask

Lid Type

The most common lid types for Iron Flask products are a flip straw, a removable straw, a flip sip lid and a screw stainless steel lid. The flip straw lids are generally the most common lids that people choose and can also be the most convenient because the straw simply flips up with the push of a button and stays secure and away from germs when laid down. But if you want more traditional lids, there are other types from which to choose. 


Similar to other water bottle brands, the common sizes for Iron Flask’s products include 14 oz, 18 oz, 32 oz, 64 oz and more. There are even gallon-sized bottles if you need a large storage unit for your food or drinks. 

What to look for in a quality Iron Flask

Vacuum insulation

Vacuum insulation allows stainless steel bottles to retain the cold or heat associated with whatever is stored inside. So if you have a hot serving of oatmeal in an Iron Flask product, that oatmeal will stay warm for hours until you’re ready to eat. Or, if you have a nice iced coffee that you want to keep cool in the heat, Iron Flask items will ensure it stays cold throughout the day. 


Stainless steel bottles tend to be free of chemicals, but some manufacturers use coatings on the inside of those types of bottles that can be harmful to your body. With Iron Flask, you can rest assured that no toxic chemicals are used in the exterior or interior, keeping your food and drinks safe. 

Wide mouth

Many Iron Flask items have a wide mouth opening, allowing you to put ice cubes, fruit slices and other objects inside the products with ease. It also makes cleaning the item easier when using a sponge or bottle brush, as you won’t have to struggle to dig your hand down the bottle just to clean it. 

Laser engraving

Many water bottles, mugs and other similar items use coated paint or some other type of coating for putting the company’s logo, a name, or other characters on the outside of the bottle. In many instances, it can result in the specific character design on the bottle coming off when washing or scrubbing the bottle. Iron Flask items use laser engraving for the designs on the outside of the bottle, so you don’t have to worry about the logo and other designs coming off. 

How much you can expect to spend on an Iron Flask

Iron Flask bottles, tumblers and mugs cost around $15-$25. The price mainly depends on what size you choose for your product, whether it’s 12 oz, 16oz, 20 oz or more. There are large-sized bottles, such as gallon-sized ones, that could cost in the $50-$60 range in a few instances.

Iron Flask FAQ

Can I put hot drinks in an Iron Flask?

A. All Iron Flask products use a premium stainless steel material that is insulated. This allows you to not only store hot drinks inside of these bottles but also retain the drink’s heat for several hours, in case you have to drive to work before you can drink your coffee or eat a meal. 

Is Iron Flask non-toxic?

A. Stainless steel is naturally BPA-free, so Iron Flask bottles are BPA-free and free of any other toxic chemicals. You’ll be able to store drinks and suitable foods inside of an Iron Flask item without having to worry about harmful toxins leaking into your food. Just make sure that you clean your bottle regularly, especially if you’re storing anything besides water inside of it. 

What’s the best Iron Flask to buy?

Top Iron Flask

Iron Flask 32 oz Sports Water Bottle

Iron Flask 32 oz Sports Water Bottle

What you need to know: If you’re not sure which size Iron Flask bottle to get, you can’t go wrong with this 32 oz bottle, as it’s not too small or big and can efficiently store a variety of foods and drinks. 

What you’ll love: It comes in various colors and patterns that offer a much more modern and stylish design than the typical water bottle. There are three lids included: a flip lid, a carabiner straw lid and a stainless steel lid. 

What you should consider: There are no notable concerns with this product. 

Where to buy: Sold by Amazon

Top Iron Flask for the money

Iron Flask 12oz Grip Coffee Mug

Iron Flask 12oz Grip Coffee Mug

What you need to know: Some people don’t want fancy water bottles and tumblers, and this coffee mug uses a traditional design if you want that classic coffee drinking experience. 

What you’ll love: The 12 oz size is perfect for when you need to store your morning coffee and can easily fit in bags, purses and work drawers for storage. 

What you should consider: The flip lid is less convenient than the lids with flip straws. 

Where to buy: Sold by Amazon

Worth checking out

Iron Flask One Gallon Sports Water Bottle

Iron Flask One Gallon Sports Water Bottle

What you need to know: For those who want something to store large amounts of water or ice for a large gathering, this gallon-sized bottle will handle all of your needs. 

What you’ll love: The heavy-duty handle allows you to hold the bottle securely and easily when it is full. Ice can stay frozen in the bottle for over 24 hours, perfect for when you want to store ice for hiking trips or other long periods.

What you should consider: The price is significantly higher than most Iron Flask products.

Where to buy: Sold by Amazon


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Ade Hennis writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.

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