Portable Liquor Tester Accurate Alcohol 0‑80% Test Meter Refractometer Tester US

Minimum Scale: 1% Alcohol. Turn the eyepiece to adjust the hand wheel to the blue and white line clear. The scale value of the dividing line is the concentration of the solution. Put the cover directly point to the light source or bright place, observe the field of view through the eyepiece.

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