The idea of using reusable containers (no plastic) instead of disposable bottles (or plastic bottle), is safely unchallenged sense. But this is nothing new and there are many manufacturers of these bottles, the best known being Sigg. Now is aluminum, which is usually the material of choice for such bottles, fall into discussions. Therefore Mizu used stainless steel. This, however, is the bottle, although slightly heavier than an aluminum bottle, but completely harmless. Since the execution of the idea is also absolutely perfect, you can only give all five stars. I hope the manufacturers will soon Mizu larger volumes (eg 1 liter) in the program.