pH Test Paper Roll: 5M Alkaline Acid Indicator Meter, Highly Versatile

8 - 11 indicates alkalinity. 12 - 14 indicates a very high level of alkalinity. 0 - 3 indicates a very acidic substance. 4 - 6 indicates an acidic substance. Can not indicate the Acid or alkali solution when its density was lower than 0.01%.

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