The YACHT has tested 18 vacuum jugs
The thermos is like eagle owl, Tes or Tempo: it is a brand name, but it is a synonym for the whole genre; the neutral designation is vacuum jug. Around 100 years after the first thermos flask, there are a number of similar brands. Their prices range from 7 euros to more than ten times. Do they keep ten times as warm?
Our test was based on the European standard 12546-1 "Insulated container for use in the household". There is a separation between vacuum jugs, "generally with a handle", and vacuum flasks, which have a narrow pouring opening. Only these must have a tight seal. On the other hand, we also examine the tightness of the lid of both variants, which is of crucial importance for on-board use.