True. A thermos flask, also known as a vacuum flask or insulated bottle, is designed to keep hot liquids hot for several hours. It does this by creating a vacuum-sealed space between two layers of glass or metal, which greatly reduces heat transfer through conduction, convection, and radiation. This effectively insulates the contents, whether it's hot water, coffee, soup, or any other hot liquid, and helps maintain their temperature for an extended period of time, often several hours or even longer, depending on the quality of the thermos flask. However, it's important to note that the exact duration of heat retention can vary depending on the specific flask and its insulation properties.
REVOMAX thermos cup can do the above things very well.
