This car antifreeze refractometer adopts imported prism for clear displays, and there is a prism cover for higher protections. ​There are five different waterlines for you to quickly and clearly view and read the different measurements.​ It only takes 2 or 3 drops and waiting a few seconds to get an accurate value.​ Support measuring specific gravities of rechargeable battery liquids, and freezing point of automobile antifreeze based on ethylene-glycol or propylene glycol, windshield wash fluids, and measuring the urea concentration in automobile diesels exhaust fluids. Features: Portable Size: ​Made from premium materials, this antifreeze tester is lightweight and portable, making it easy to carry and easy to use.​ Quality Prism: Imported prism is used for clear display, and there is a prism cover for higher protections. Digital Display: ​There are five different waterlines for you to quickly and clearly view and read the different measurements.​ Calibration Knob: ​Equipped with an adjustment screw, this is a calibration knob that precisely adjusts the viewing angle.​ Adjustable Focal Point: The focal point is adjustable in design, and you can rotate the eyepiece to adjust the focal point for more accurate measurements.​ Quick Measurement: It only takes 2 or 3 drops and waiting a few seconds to get an accurate value.​ Wide Applications: Support measuring specific gravities of rechargeable battery liquids of 1.10-1.40SG, and freezing point of automobile antifreeze based on ethylene-glycol or propylene glycol: -50 to 0 ℃, windshield wash fluids: -40 to 0 ℃, and measuring the urea concentration in automobile diesels exhaust fluids: 30% to 35% Specifications: Name: Car Antifreeze Refractometer Material: ABS Package size: 180 * 45 * 40mm / 7.09 * 1.77 * 1.57in Package weight: 88g / 3.10ounce Packing List: 1 * Car Antifreeze Refractometer 1 * Storage Bag 1 * Wiping Cloth 1 * Guideline