Our products are considered medical-grade for a couple of reasons, to begin with, they are designed to prevent any substance from dissolving with the medicine. there is more to it and will get back to it later...That, coupled with FDA certified materials is what we base the definition of a medical device. we still don't know the implications of exposure to toxic materials from paraphernalia as there is no research yet to be made, if any, this will take some time.back to the design, as grinder tend to clog from trichomes quite fast and degradation will occur once the frictions increases we looked for a weak link to protect the main grinder parts and to isolate the grinding chamber. The ring is placed in a channel and the friction is within the channel, 2 walls away from the medicine. The ring is also is softer than the main grinder parts so when it degrades; it will be more likely to tear than to shred micro "dust" particles.this is how our unique mechanical design captures any substance apart from the main grinding chamber, delivering nothing but pure medicine.