ANTIFREEZE REFRACTOMETER 4 IN 1 Function: ●Measuring specific gravity of rechargeable battery acid: 1.100~1.400kg/L, ●and freezing point of automobile antifreeze based on ethylene glycol or propylene glycol : 58℉ to 32℉/-50 to 0 ℃, ●windshield wash Fluid (SRF1): -40℉ to 32℉/ -40 to 0 ℃, ●Adblue the Urea Concentration in automobile diesel exhaust fluid (DEF) :30% to 35% Quick & Easier: Just 2 or 3 drops and wait for few seconds and get the accurate value. Optic lens no battery required, less samples than a traditional Hydrometer, more affordable than a digital meter. Automatic Temperature Compensation: The antifreeze coolant tester with ATC function, which can automatically compensate the temperature when ambient temperature changes, excellent eliminate the deviation, quickly and easier get the precise data. Portable & Durable: This antifreeze tester is made of non-staining aluminum and ABS rubber, durable and resistant to abrasion. Lightweight and convenient to carry and easy to use. Car Owners’ Helper: The optics antifreeze test is a convenient tool can help you to check your automobiles’ battery fluid battery acid, antifreeze coolant, windshield water fluid and Adblue to protect your cars.