Steel Flask

 Coffee Urns  meant to maintain liquids at a constant temperature for a lengthy amount of time. It is frequently used to keep hot liquids warm and cold liquids cold.A Thermo Flask is made up of two layers of glass or stainless steel with a vacuum between them. This material works as insulation, reducing heat transfer between the flasks inside and outside. To improve heat retention, the inner layer is frequently covered with a reflective substance.