Keep liquids hot or cold for longer, with the 500ml vacuum flask from Olympia. The flask's vacuum seal is specially designed to lock-in heat! Not only does this help to regulate your drinks' temperature, but also its flavour and aroma - allowing you to enjoy your hot beverages for longer, without losing any taste. Plus, the locking lid helps to keep your drinks that-bit more secure, whilst ensuring controlled pouring! This prevents leaking during transportation and makes it easy to pour a fresh coffee or cuppa. And completed with a cup that doubles-up as a lid, the flask is an excellent space-saving solution to carry in your bag or sit on your desk, whilst making it easy to grab a quick drink on-the-go. What is a vacuum flask and how does it work? A vacuum flask is a vessel that helps keep your hot drinks warmer for longer, and your cold drinks cooler for longer. It works by preventing heat leaving - or entering - the flask in three ways. Firstly, the inside is coated with a silver finish that prevents heat radiating out, or, in the case of chilled drinks, radiating in. Next, the double wall design creates a pocket of air between the inner surface and the outer one. This prevents heat loss - or gain - via conduction, which happens when two surfaces touch. Think burning your hand when touching a hot surface. That's conduction! The last way vacuum flasks retain heat is by stopping convection - or the movement of heat through gas or liquid. The airtight lid of a vacuum flask prevents this happening by stopping air entering or leaving the vessel. How do you use a vacuum flask? Although it might seem straightforward, there are a few ways to maximise the effectiveness of your vacuum flask. Firstly, heat it before pouring your beverage in! To do this, simply fill with boiling water and allow it to sit for a few minutes. Next, pour in your tea, coffee, soup or other liquid and make sure the lid is screwed on tight. This will keep it piping hot - or refreshin
