Product review (1 stars): Bad Chinese Knock-offs
Do NOT, I repeat, DO NOT buy these.  Apparently they are a low-quality knockoff from China.  I called One Purify and they said there was a rash of similar knockoffs being sold.  You can tell because the packaging doesn't have the "TM" trademark symbol by their name.  They sound like machine guns in my frig.  I followed the instructions and they still did it.  Don't believe me?  Call 1.713.955.2777 and talk to their people about it.