SinoWare Digital pH Tester
Digital pH Tester by Sinoware. Large LCD screen. .01 pH resolution. Accuracy .05 pH. Measurement Range 0-14 pH. Features ATC (automatic temperature compensation between 32 and 122 deg F). Replaceable electrode. Includes meter, 4 x 1.5v button cell batteries, adjustment screwdriver, carrying case and manual.
You can use a pH meter to check the pH of your water, mash, [test Star San effectiveness] and finished beer.
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Bought one at $10 the last time around. Huge improvement over strips and allows me to build my water profile from RO.