This FLSK water bottle might be the best thermal bottle for hot and cold drinks

T3 tried the FLSK drinking bottle to see if its thermal technology lived up to the hype. Here’s what we found…

FLSK drinking bottle review
(Image credit: FLSK)
T3 Verdict

With its attractive design and easy portability, the FLSK stainless steel drinking bottle does everything you need a water bottle to do. What sets it apart from other reusable water bottles is its thermal technology which keeps hot drinks hot and cold drinks cold for hours on end.

Reasons to buy
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    Attractive design made of high quality stainless steel

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    Keeps water cold and hot for hours!

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    Easy to travel with and take with you everywhere

Reasons to avoid
  • -

    Similar design to many other brands

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    Spills if you fill it up too high

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In T3’s FLSK stainless steel drinking bottle review, I put this stylish water bottle to the test to see if its thermal technology lived up to the hype.

FLSK is a German brand that designs and manufactures water bottles and cups. With a focus on sustainability, FLSK uses high quality stainless steel materials to make reusable alternatives to plastic products. Sustainability is what most people are looking for when it comes to buying the best water bottle, and FLSK offers this entirely with its range of drinking bottles.

Not only is FLSK focused on environmentally-friendly products, but its FLSK drinking bottle uses VICC technology to keeps drinks ice cold for up to 24 hours or hot for up to 18 hours. Here's what I found when I tried out the FLSK drinking bottle.

FLSK drinking bottle review: Unboxing & design

The FLSK drinking bottle comes in a cylindrical cardboard box which can be recycled and the bottle has little to no packaging around it, so straightaway, FLSK is showing off its sustainability credentials. The version I was sent was the 500ml bottle in the MDNGHT colour which costs £39 or you can choose the 750ml for £47 and the 1000ml for £54.

Made of stainless steel, the FLSK drinking bottle has a simple yet sleek design that’s not too dissimilar to other water bottles from S’Well and Hydro Flask. The bottom of the bottle and the lid feature small FLSK logos and there are nine neutral colours to choose from.

FLSK drinking bottle review

(Image credit: Beth Girdler-Maslen / T3)

FLSK drinking bottle review: Performance

When it comes to reviewing a water bottle, it’s a pretty straightforward task. The only real questions that need answering are if the bottle holds water well and if it leaks. The answer to these two questions are yes: the FLSK drinking bottle holds a good amount of water and it has a leak-proof lid that keeps drinks at their optimal temperature and prevents spills… as long as you don’t fill the bottle too high up the neck.

The most impressive thing about the FLSK drinking bottle is its VICC technology which perfectly insulates the water inside it, keeping your cold drinks icy cold and your hot drinks boiling hot for hours. FLSK states that it can keep water at cold temperatures for 24 hours and I definitely found this to be the case. I take a water bottle to bed with me every night and the water inside the FLSK drinking bottle was still very cold when I woke up in the morning and stayed that way throughout the day.

The same can be said about hot water, which FLSK states it can keep hot for 18 hours. I filled the FLSK drinking bottle with boiling water from a kettle and found it to still be burning hot hours later (my pinky finger wasn’t too impressed by this though). The exterior of the bottle stayed cool despite the hot water inside so you’re unlikely to burn your hands on it, although the lid does get a bit warm. It’s a good option if you’re looking for the best water bottle for hiking.

As the FLSK drinking bottle has a maximum height of 25.5cm, it easily fits into any bag or best backpack, making it super easy to carry around with you. I’d definitely recommend it for hiking, camping and any other trips you might be taking. 

FLSK drinking bottle review

(Image credit: Beth Girdler-Maslen / T3)

FLSK drinking bottle review: Verdict

Overall, the FLSK drinking bottle does a great job at keeping your drinks at the perfect temperature. I was most impressed by its insulation for both hot and cold beverages and think it's something to consider if you’re going hiking or camping. The leak-proof lid never failed me and if you’re trying to be more sustainable and ditch plastic water bottles, FLSK is a good brand to buy from.

The only negatives I have is the FLSK drinking bottle has a similar design to other water bottles on the market, and compared to options from S’Well and Hydro Flask, it’s slightly pricier. However, you’re paying for longevity and durability which is hard to fault.

Bethan Girdler-Maslen
Home Editor

Beth is Home Editor for T3, looking after style, living and wellness. From the comfiest mattresses to what strange things you can cook in an air fryer, Beth covers sleep, yoga, smart home, coffee machines, grooming tools, fragrances, gardening and much more. If it's something that goes in your house, chances are Beth knows about it and has the latest reviews and recommendations! She's also in the know about the latest deals and discount codes from top brands and retailers.

Having always been passionate about writing, she’s written for websites, newspapers and magazines on a variety of topics, from jewellery and culture, to food and telecoms. You can find her work across numerous sites, including Wedding Ideas Magazine, Health & Wellbeing, The Bristol Post, Fashion & Style Directory, TechRadar, CreativeBloq and more. In her spare time, Beth enjoys running, reading, baking and attempting craft projects that will probably end in disaster!