Dr Meter PH003 pH Meter.  Clear Backlit LCD Display.  Measure Range: 0.00-14.00 pH.  Resolution: 0. 01 pH, accuracy: ±0.05 pH.  Auto calibration.  Includes pH meter, 2 x LR44 batteries, 3 x Buff Powder, manual and carrying case.

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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Dr.meter PH003 Digital pH Meter pH Tester with pH buffer powder pH Test Strips Auto Calibration Button 0-14 pH Testing, Aquarium, Water, Swimming Pool, Hydroponics