Chris Townsend looks at Hydro Flask’s lightweight insulated flask

Hydro Flask makes a range of insulated flasks that don’t look like insulated flasks. Instead they look like water bottles and come in a wide range of colours. They don’t come with cups either but have a range of different screw-tops. If you don’t want to drink straight from the bottle you’ll need to carry a mug as well. Also unlike most insulated flasks Hydro Flask puts as much emphasis on keeping drinks cold as keeping them hot. This is not something that’s a big concern for much of the year in the British hills!Hydro Flask

From the range I’ve tested the Hydro Flask 21oz bottle, the name showing the American origins. For those of us who don’t think of liquids in terms of fluid ounces this equates to 621ml or just over a pint. The test bottle weighs 359g, a little more than the claimed 295g but still quite light for the capacity. (The lightweight 470ml insulated flask that I’ve used regularly for many years weighs 279g without the cup). The Hydro Flask is made from double-wall stainless steel and has a matte finish with a ‘proprietary powder coat’ that gives a rough non-slippery feel. The lid has a flexible handle.

The flask is claimed to be able keep drinks piping hot for 12 hours and icy cold for 24 hours. My use of it shows that the first is certainly true. After 12 hours boiling liquid was still hot enough to need sipping rather than gulping. After 24 hours it was lukewarm. As to keeping drinks cold, at present anything would keep them cold indefinitely! As expected with stainless steel the flask doesn’t hold flavours or taint the contents.

The Hydro Flask is slim and fits easily into a pack pocket. I like the secure feel and the light weight. A mug will fit clumsily over either end, though this does somewhat detract from the clean appearance. The Hydro Flask is fine for cold weather use. I carry an insulated flask on day walks from October through May and sometimes on overnight trips in really cold weather. I don’t carry one in summer – keeping drinks cold isn’t a problem – but I know those who do as they can’t be without hot tea whatever the weather. If I was looking for an insulated flask I’d certainly consider the Hydro Flask.