This Themoskanne is excellent and can be recommended without reservation. I've been looking for an easy and good insulating Themoskanne for mountaineering and ski touring. And the pot is relatively easy, in fact, all locks can be optimally operate and maintain absolutely tight, even if you put the jug on her head. But what has pleased me most is the extremely good insulation. I have the bottle in the afternoon filled with boiling water and then for 25 hours on the balcony at minus 16 degrees Celsius (February 2012) provided. After 14 hours the water with 75 degrees was still hot, and after a further 11 hours, the water was still nice and warm at 50 degrees Celsius. At higher outdoor temperatures the pot holds further warm longer.