Nothing beats a hot brew on a chilly day in the hills, and the best way to keep your tea, coffee or soup steaming hot is by packing a good thermos flask in your rucksack. All insulated flasks work on the same basic principle. They use a double-wall construction, separated by an airless cavity, which creates a thermal insulation layer that keeps liquids hot for longer. The same vacuum principle applies to keeping drinks cold, so double-walled flasks are also a great way to keep drinks ice-cold on a hot hiking day. We’ve a selection of the best thermos flasks, ranging in size from 470ml to 1 litre. Bigger flasks always retain heat better than smaller flasks, but are typically bulkier and heavier.

• Thermos Vacuum Insulation: Advanced technology in this thermos food jar keeps your meals hot for 14 hours or cold for 24, ensuring ideal temperature for various activities
• Durable Construction: This insulated food container features robust stainless steel interior and exterior that withstand daily use and maintain temperature control
• Versatile Lid Design: Insulated lid of this thermos food container doubles as a convenient bowl, reducing the need for extra dishes and making it easy to enjoy your meals anywhere, anytime
• Temperature Control: This lunch thermos remains cool to touch with hot contents and sweat-proof with cold, providing safe handling and preventing messy condensation on surfaces
• User-Friendly Features: This insulated food jar’s wide mouth design allows for easy filling, eating, and cleaning, making it a practical choice for daily meal prep and on-the-go dining