Thanks to this refractometer, you can easily check the quality of the grapes and thus better brew your wine! The refractometer is mainly developed to test the sugar content of original grape juice, and then to determine the potential alcohol content of grape wine, fermented grape juice. It cannot be used to measure the alcohol content of wine. Measurement range: Brix (mas sacch): 0-40%, alcohol: 0-25, Resolution: Brix (mas sacch): 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 20C, automatic temperature compensation between 10C and 30C (ATC) Sharp precision measurement dividing line (blue-white ), easy to read (daylight visible), adjustable eyepiece for focus adjustment Calibration: zero calibration with distilled water at 20C, automatic temperature compensation between 10 C and 30C (ATC). Product Description: Refractometers provide fast and accurate information on the sugar content of grapes and grape musts, berries, pome and stone fruits, as well as unfermented grape juice. After the sample is applied to the prism, the refractometer's special optics create opposing fields of light and of darkness. 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 fruits - Determine the progress of harvest maturation - Measure the progress of fermentation - The amount of sugar present as well as the alcohol concentration in the grapes measure - Let the winemakers determine if the fruit is at peak maturity and should be harvested. Measurement range: 0-40% brix (mas sacch), 0-25% alcohol Resolution: 0.2% brix (mas sacch), 0.2% alcohol Accessories: pipette, cleaning cloth, screwdriver and carrying case. With this refractometer you can easily check the quality of grapes and brew your wine better!