Beware that there is a manufacturing issue with the cap plastic of the Pro bottle that Kavafied is selling. I have limited manufacturing experience but it appears that there is either a problem with the plastic compound itself, or that the material is not being melted uniformly while in the mold, because there is a thin outer skin of plastic that degrades due to the expected mild abrasion of blending with aluballs. The result is a non-trivial amount of plastic flecks shedding into your drink that you are bound to then consume unless you re-strain what comes out of the bottle - defeating the purpose of the bottle. I tried to reach out to Kavafied using the same method I've had prior comms with them, Facebook Messenger, my messages were seen yesterday morning, and I've gotten no response. So just a warning that at least the black plastic caps, if not the other colors, may have this problem. I can't imagine mine is a fluke since it looks like a pretty straightforward manufacturing problem. There are numerous other problems with both of their bottles (pro and regular), but at least none of the other problems are actual health hazards like this one, so perhaps I'll save those for another post. From now on I'll only buy powders and aluballs from this vendor.