In our family currently get two of Mizu bottles used (M8 Nixon Camo Glossy Blue and Burton Performer / Black). It is positive that they are made of stainless steel and have no interior coating. The paint outside is not particularly shockproof at least at the Camo Glossy Blue, so that after a few weeks a small area is blank. But that does not really bother. The shutter opening is relatively large, but still OK to drink. Even if the bottle is dishwasher safe, they should not be too frequently in the dishwasher with regard to the finish.
