What is a Vacuum Flask?

One of the best ways to keep your cold drinks cold and your hot drinks hot is a vacuum flask. Invented by Sir James Dewar in 1892, the vacuum flask consists of a large outer vessel and a small inner vessel, both joined at the neck. All air is removed from the space between these two vessels, creating a vacuum. This vacuum acts as an extremely efficient thermal insulator, vastly slowing the rate at which the flask's hot contents cool down, or cold contents warm up. Older model vacuum flasks tended to have an outer metal flask and a glass inner flask, but with modern flasks, both vessels are made of metal, making it easier to clean the inner vessel without the risk of breakage.

Don't You Mean Thermos?

Vacuum flasks are sometimes wrongly called 'Thermos' flasks. This is the name of a specific brand of vacuum flask, and most vacuum flasks are not made by Thermos. In fact, our non-Thermos brand vacuum flasks are highly efficient ways to keep your drink stored and we even supply them in promotional gift sets perfect for the holiday season.