describe With this refractometer, you can easily check the quality of your grapes to make your wine better! The refractometer is mainly used to detect the sugar content of the original grape juice, and then to determine the potential alcohol content of wine and fermented grape juice. It cannot be used to measure the alcohol content of wine. Measuring range: Brix (mas sacch): 0-32%, 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 view the Brix reading through the window; Calibration: Zero calibration with water at 20°C, automatic temperature compensation between 10°C and 30°C (ATC) Clear and precise measuring dividing line (blue-white), easy to read (visible in daylight), adjustable sight glass for focusing Calibration: 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 must, berries, pears and stone fruits, and unfermented must. Once the sample is applied to the prism, the refractometer's special optics produce light and dark fields opposites. The border between the two fields represents the sugar content of the sample. With a refractometer, you can: - Measure the Brix percentage of grapes or other fresh fruit - Determine the ripening progress of crops - Measure the progress of fermentation - Measure the sugar content and alcohol concentration in grapes - Allow winemakers to determine if the fruit is ripe and should be harvested.