1. This refractometer can be used to check the quality of grapes and assist in wine making. It is mainly used to measure the sugar content in original grape juice and further determine the potential alcohol content in fermented grape juice (wine). It cannot be used to measure the alcohol content in finished wine. Measuring range: Brix (mass saccharide): 0-40%, alcohol: 0-25%; Resolution: Brix (mass saccharide): 0.2%, alcohol: 0.2%. 2. Easy to use: Place 2-3 drops of sample on the main prism, close the plate, and observe the Brix value through the window. CALIBRATION: Zero calibration with water at 20°C, with automatic temperature compensation (ATC) between 10°C and 30°C. 3. Features a precise measuring dividing line (blue-white), easy to read under daylight, and an adjustable eyepiece for focus adjustment. 4. Calibration: Zero calibration with distilled water at 20°C, with automatic temperature compensation (ATC) ranging from 10°C to 30°C. 5. Product description: Refractometers provide information on the sugar content of grapes, grape must, berries, seed and stone fruits, as well as unfermented grape juice. When a sample is placed on the prism, the refractometer's special optics create contrasting light and dark fields. The edge between these two fields indicates the sugar content in the sample. 6. Functions of this refractometer include: - measuring the Brix percentage of grapes or other fresh fruits; - determining the progress of samples. It can be applied in harvesting (measuring the fermentation process, measuring the sugar content and potential alcohol content in grapes) and consulting winemakers on whether the fruits are ripe for harvesting. 7. Measuring range: 0-40% Brix, 0-25% alcohol. 8. Resolution: 0.2% Brix, 0.2% alcohol. 9. Accessories: pipette, cleaning cloth, screwdriver, and case. 10. This refractometer can be used to check the quality of grapes and assist in wine making.