Product review (3 stars): No instructions included
This was supposedly sold and shipped by Amazon, but still, I am wondering if it genuine.  There were NO instructions either in the box or on the box.  I unscrewed the old one, and installed the new one, and I am glad that I thought to flush it before drinking, because the first glass of water I drew had black stuff in it.  After I saw that, I drew about 10 glasses more, and after the second glass they were all clear, so I suppose it is OK now.  I can't imagine why there were no instructions with this!