The body of the thermos flask is made of grey and maroon urea formaldehyde and is lined with glas. The glas encloses a vacuum which keeps the contents hot, and as the materials of the flask are poor conductors of heat, this also helps to maintain the temperature of the liquid in the flask. This flask has an arched handle, with the stopper visible. Model no 65, refill no 14F, made in England by Thermos Ltd.
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