Thermos Stainless King Food Flask (470ml) review: an excellent flask for mid-hike meals

Feast on hot food on your walks with this wide-mouthed Thermos Stainless King Food Flask

Thermos Stainless King Food Flask (470ml)
(Image: © Thermos)

Advnture Verdict

While not ideal for drinks, the King is excellent for keeping food lovely and warm for a properly restorative mid-hike meal on the trail.


  • +

    Folding spoon in lid

  • +

    Insulated lid serves as a bowl

  • +

    Excellent insulation

  • +

    Easy access to eat from the pot

  • +

    Easy to clean


  • -

    Not ideal for drinks

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    Squat dimensions

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First impressions

Warning. The Thermos Stainless King Food Flask can seriously strain friendships. Nothing is more likely to turn your walking buddies green with envy than you tucking into a hot meal while they chomp on soggy sandwiches. Pasta with pesto and cheese, chunky soups and hearty stews… whatever your midday masterpiece, this robust Thermos Stainless King Food Flask will keep it hot until it’s time for lunch.

The flask itself is short and fat – its 9.4cm diameter makes it too wide to slide into a side pocket of a rucksack, but at only 14.2cm tall it squeezes inside a pack with no trouble. The lid conceals a handy, full-size folding spoon and you can use the insulated lid as a bowl if you’re sharing your meal, although it’s not very deep (and most hungry walkers should be able to manage the full contents of the flask on their own).

Thermos claims that, once sealed, the Stainless King Food Flask will keep heated food hot for nine hours, and cold food chilled for 14 hours.


RRP: £22 (UK) / $24 (US)
Volume: 470ml / 16fl oz
Weight (empty): 380g / 13.4oz
Height: 14.2cm / 5.6in
Lid-opening style: Screw-in stopper
Colors: Matt Black / Midnight Blue / Red / Copper / Gunmetal / Duck Egg / Raspberry / Matt Black & Gold

In the field

This is another product that I have been testing for some time, and the dings and dents in my flask reflect not only the King’s tough life on the trail at weekends, but also Monday to Friday school lunch duties, for which it’s filled with pasta and sauce.

Even after two years’ tough use, boiling water cooled only to 70°C after four hours when we subjected the King to the same test we put all of our flasks through – which is impressive. For optimum performance, I have discovered that it pays to pre-heat the flask with boiling water prior to filling it with food.

Be warned: once the wide lid is removed it doesn’t take long for an icy wind to cool food down, because of the wide mouth. This same wide mouth does, however, make this pot easy to clean – only larger hands won’t fit inside it, and the five-year guarantee is a welcome case of a manufacturer putting its money where its mouth is.

Since I started using the Thermos Stainless King Food Flask, I have swapped the folding plastic spoon it comes with for a folding metal spoon, which is far better.

Jonathan Manning

After spending a decade as editor of Country Walking, the UK’s biggest-selling walking magazine, Jonathan moved to edit Outdoor Fitness magazine, adding adrenaline to his adventures and expeditions. He has hiked stages or completed all of the UK's national trails, but was once overtaken by three Smurfs, a cross-dressing Little Bo Peep, and a pair of Teletubbies on an ascent of Snowdon. (Turns out they were soldiers on a fundraising mission.)