Vacuum Flask

The vacuum flask really consists of two bottles, one inside the other, the air being extracted from the space between, forming a vacuum, which is a non-conductor of heat. The temperature in the corked up inner bottle this remains the same, whatever the temperature outside may be, keeping the contents hot or cold as desired. The outer case is simply for protection against breakage. - There is a border around the image. Image size is correct. Many sizes available.