A year ago we bought the "big brother", the 1.2l vacuum flask. This bottle already inspired us with fantastic warming periods (morning hot tea filled - 6 hours later still so hot that you can drink it immediately). Even the two integrated cups are well resolved - not great, but innovatively packaged in another. Now we have ordered the smaller version and four weeks ago also in use. Both versions are close to 100% - and both hot and cold drinks. Did such as sparkling water bottled in the bottle and after hours, the content was still super cold, but also the carbon dioxide was still included. Even under these extreme pressure conditions inside the bottle the closure was absolutely tight. Our experience: The rotation lock this IsoCup flasks are not as quick to open like a quick - but keep much longer the contents hot / cold and are truly 100% leak-proof!
