I was skeptical at first whether the system really works - completely wrongly. In relation to the hot water - cold water mixing method of the container requires much less space in the diaper bag. The set consists of a plastic container and a thermos. The jug can be kept in plastic containers. The application is simple. At home it infects the thermos with hot water and screwed the pot in the plastic container. Should the bottle be warmed, poured the hot water of the pot in the plastic container presents into the milk bottle and screwed the lid. The container can how long the bottle now be reheated must read it - for example, 150 ml are heated for 2 minutes. The milk then pleasant drinking temperature. Then the hot water can be placed back into the thermos and possibly used a 2nd time. Works great, because the thermos keeps the water hotter for longer. I use the bottle warmer on a regular basis and am very satisfied!