Poit PH-02 P-type PH Meter Tester. .005 accuracy, .01 resolution, 0-14 pH range. ATC (automatic temperature correction). One touch calibration button. Comes with meter, 3 x 1.5 LR44 batteries, 3 x pH buffer powders.
You can use a pH meter to check the pH of your water, mash, [test Star San effectiveness] and finished beer.