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Works great, but you can get the job done much cheaper by just buying citric acid at your local grocers in bulk bags. I also use citric acid to clean up the hard water in the washroom shower doors etc... wherever there is build up
This product came with no instructions -- just individual packets each covered with Japanese -- the box as shown online with English on it did not come -- false advertising. So we're having to do more research on how to use it.