I bought these to test the pH of hair products I use in the salon and they worked really well. I wish the instructions were in both English and Chinese, which they were. I would also like the color of some pH values to be more different from the color of the test strips. In particular, the color of the pH 5 value is VERY close to the yellowish color of the test strip, making it difficult to determine the exact pH value. However, I have found that some products definitely fall into the alkaline range, which I was trying to recognize as I don't want to apply styling products with a pH above 7 on freshly colored hair, on any hair but especially colored hair. They are very affordable and did what I wanted.
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