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Kit review: Hydro Flask

Written by Fiona

August 24 2019

I have been testing Hydro Flasks – for both hot and cold drinks – in a range of outdoors places. There are different versions, including an 18oz and 21oz and also a 32oz wide-mouthed Hydro Flask.

The Hydro Flasks are vacuum insulated stainless steel bottles. They immediately appeal to me because of the look of them. The collection includes some brilliantly bright colours and the flasks have a modern and funky design. They are a 21st reinvention of the old-fashioned coffee flask!

I also like the versatility of the flask. The label told me that it would keep cold drinks icy cold for 24 hours and hot drinks piping hot for six hours.

In addition, the flasks have:

  • A looped sports cap that is easy to open and close and also aids carrying the flask when the cap is on.
  • TempShield to stop the heat or cold from inside burning your hands on the outside
  • Sweat-free powder coat to prevent you losing grip of the flask.
  • The 36oz wide-mouth Hydro Flask has a straw in the lid, too.
A coffee stop during a walk in the Kilpatrick Hills.
A coffee stop during a walk in the Kilpatrick Hills.
36oz wide-mouth Hydro Flask.

On test: Hydro Flasks

I have carried coffee and ice-cold water in the 18oz and 21oz flasks. I have used the 180z flask for shorter adventures and the 21oz when I need more liquids.

I can confirm that the flask does a good job of keeping things hot or cold. The coffee actually stayed hot for far longer than six hours. You do need to fill the flask to the top for this to happen. The cold drink, mixed with ice, stayed icy cold for 24 hours.

I love the look and feel of the flasks and they have become my first choice when heading off for a hill or mountain hike, or a trip in the campervan.

I have also found the cap is easy to open and seal again and the non-slip paint coating does exactly as it says it will.

Walking Munros with a Hydro Flask of cold juice.
Walking Munros with a Hydro Flask of cold juice.

The flasks are really strong and durable. They look and feel as though they would last for many, many years. I think that in time I will like mine even more because the stainless still will start to look a little rough around the edges and this will show that it has been well used. Just now – and after about 10 outings – it still looks very shiny new!

The 18oz Hydro Flask fits neatly into the side pocket of my summer walking rucksack.
The 18oz Hydro Flask fits neatly into the side pocket of my summer walking rucksack.

What I am not so keen on is the weight of the flask. It’s fine for walking but I would not carry it in a rucksack when running as it would be too heavy. I would choose, instead, to carry a basic lightweight plastic bottle and put up with the liquid becoming warm.

The wide drinking top – even the standard mouth width – also takes a bit of getting used to. If you tip the bottle up too quickly or too high, the liquid spills out the side of your mouth. It took me a few goes to get the angle just right.

A strong, robust and funky design.
A strong, robust and funky design.

However, when it comes to cleaning, it is far better to have a wider bottle mouth and I have found that it washes well upside down in the dishwasher.

You also need to be careful when drinking piping hot liquids straight from the flask. It is a better idea to pour into a mug. There is a Hydro Flask insulated mug for this purpose, too.

You can buy the 18oz Hydro Flasks with a standard mouth from Tiso for £23.

There are also sizes 21oz, 24oz, 32oz, 40oz and 64oz. I like the look of the coffee flasks and also the beer flasks, too! See Hydro Flask.

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