So popular that its brand name is now a generic term for any vacuum bottle, a Thermos beverage container is the obvious first choice for keeping drinks hot or cold. Durable and reliable, they're great for all kinds of liquids, retaining their temperature all day.
Before choosing a Thermos, first consider what you need from a beverage container. Do you want to keep drinks hot or cold? What capacity do you require? If you're looking for a large flask for hot and cold drinks, the Thermos Stainless King Vacuum-Insulated Beverage Bottle is ideal.
A Thermos doesn't heat or chill its contents. Instead, it retains the temperature of whatever liquid you put inside. So, it keeps cold drinks cool and hot drinks warm. Most work for hot and cold drinks, but some are suitable for cold drinks only.
The smallest Thermoses hold around 12 ounces, while the largest can hold up to 68 ounces.
While Thermos containers used to have glass inserts, they're now primarily made from stainless steel, with plastic stoppers and occasionally plastic lids. This makes them significantly more durable than old-style vacuum flasks.
The last thing you want is your Thermos leaking into your bag or all over the passenger seat of your car. Most are completely leak-proof, as long as you close the lid properly, so there's no need to worry about making a mess.
Some flasks come with a lid that doubles as a drinking cup. Occasionally, they even have double-stacked lids to act as two cups. This saves you from carrying around a mug or glass for drinking.
Due to the vacuum insulation, Thermos containers are sweat-proof, so you don't get annoying condensation on the exterior when you put cold liquids inside.
For the same reason they don't sweat, these containers remain cool to the touch, no matter how hot the liquid inside is.
You can find Thermoses in a wide range of colors. Those made for kids even feature popular cartoons, movies and video game characters.
Small cold-only containers start at around $10-$15, while the largest hot-and-cold versions cost roughly $35-$45.
A. Thermoses are made using food-grade stainless steel, which is completely safe at all temperatures. It doesn't leach any chemicals into your drink and is easy to clean, so it won't hold onto particles of old drinks that affect the taste of your beverages. It's also not a good environment for mold or mildew to develop, so you shouldn't have any issues with them in your container.
A. Some are dishwasher-safe, but others aren't, so check the manual before you clean yours this way. Those that can go in the dishwasher should usually go on the top rack, where they'll get a more gentle clean. That said, you may find your container stays in better condition for longer if you wash it by hand. You can use a bottle brush to more effectively clean the interior.
Thermos Stainless King Vacuum-Insulated Beverage Bottle
What you need to know: Thanks to its large capacity, this container can keep you in hot or cold drinks all day.
What you'll love: The twist-and-pour stopper lets you pour drinks without removing the stopper completely. The stopper is leak-proof, and the lid doubles as a drinking cup. It's dishwasher-safe on the top rack. It comes in 40-ounce and 68-ounce versions.
What you should consider: It has very few flaws, although a small number of buyers report receiving their flask dented slightly.
Where to buy: Sold by Amazon
Thermos Funtainer Vacuum-Insulated Kids' Straw Bottle
What you need to know: This compact 12-ounce bottle with built-in drinking straw is perfect for kids.
What you'll love: It's great for kids because it's easy to carry and open. It comes in numerous colors and designs, including Pokemon and Super Mario versions. It keeps drinks cool for up to 12 hours.
What you should consider: It isn't suitable for hot beverages.
Where to buy: Sold by Amazon
Thermos the Rock Vacuum-Insulated Beverage Bottle
What you need to know: Large and rugged, this flask holds 44 ounces and feels solidly made.
What you'll love: It has a durable handle with a non-slip grip. It keeps hot drinks warm for 12 hours and cold drinks cool for 24 hours. It comes with a lid that you can use as a drinking cup.
What you should consider: The inside of the cup is plastic, which some people would rather not drink from directly.
Where to buy: Sold by Amazon
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Lauren Corona writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.