30-Pack Color-Coded Buffer Calibration Tablets 4, 7, 10 for Electronic pH Meters

Dissolve one pHbuffer tablet in 20 mL of deionized water. This also enables these pH tables to have an industry leading margin of error (+/-. 05 pH for each tablet). pH 10 will produce a green solution, pH 7 will produce a yellow solution, and pH 4 will produce a pink solution.

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