With this refractometer, you can easily check the quality of grapes and thus brew your wine better! The refractometer is mainly developed to test the sugar content of the original grape juice, and then to determine the potential alcohol content of grape wine, the fermented grape juice. It cannot be used to measure the alcohol content of wine.Measuring range: Brix (sacchar): 0-32%, alcohol: 0-25, Resolution: Brix (sacchar): 0.2%, alcohol: 0.2%Easy to use. Place 2, 3 drops of sample on the main prism, close the plate and look through the window at the Brix reading; CALIBRATION: Zero calibration with water at 20 C, automatic temperature compensation between 10 C and 30 C (ATC)Precision measurement Sharp dividing line (blue-white), easy to read (daylight visible), adjustable eyepiece for focus adjustmentcalibration: Zero calibration with distilled water at 20 C, automatic temperature compensation between 10 C and 30 C (ATC).Product description:Refractometers provide fast and accurate information on the sugar content of grapes and grapefruit, berries, pomegranates and stone fruits, as well as unfermented grape juice.After applying the sample to the prism, the special optics of the refractometer create opposing fields of light and dark. The boundary between the two fields indicates the sugar content of the sample. With the refractometer you can: - Measure the Brix percentage of grapes or other fresh fruit - Determine the progress of harvest ripening - Measure the progress of fermentation - The amount of sugar present as well as the alcohol concentration in the grapes measured - Let winemakers determine if the fruit is at its peak of ripeness and should be harvested.