The red litmus will turn blue when it comes into contact with an alkaline solution above pH 6.8. Supplied in plastic snap-cap container, 100 paper strips per container! Litmus paper is NOT used to determine the pH level of a solution.
The BLUE litmus will turn RED when it comes into contact with an alkaline solution below pH 6.8. Supplied in plastic snap-cap container, 100 paper strips per container! Litmus paper is NOT used to determine the pH level of a solution.
Top Grade Manual Phoropter Features: -Unique design of butterfly-shape appearance; -Capable of checking up all-sides visual functions,accurate and comfortable in measurement; -Exquisite manufacturing technique with comfortable feel; -High grade plated-film used in all optic lenses.
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