Product description Glycol antifreeze freezing point: -50 ~ 0, division value of 1 Freezing point of the propylene glycol antifreeze: -50 ~ 0, division value of 1 Specific weight of the electrolyte: 1.10-1.40, index value 0.01. (1.15 ~ 1.20 requires charging; 1.20 ~ 1.25 sufficient power; 1.25 ~ 1.30 sufficient power) Glass cleaning fluid freezing point: -40 +0, division value of 5 Contain: 1 * refractometer 1 * screwdriver 1 * manual 1 * cleaning cloth 1. USE: This refractometer allows you to determine the ethylene glycol and propylene glycol concentration of antifreeze in your vehicle, solar system, heat pumps, freezing point of windshield washer fluid, heating system, or other machines or systems. 2. MEASURING RANGE: Ethylene glycol (ethylene glycol): -50��C to 0��C; Propylene glycol (propylene glycol): -50��C to 0��C; Windscreen washer fluid - ethanol + water: -40��C to 0��C; Propylene glycol + water SRF1): -40��C to 0��C. Urea concentration 30%-35%, battery acid from 1.10 to 1.40 kg/L. 3. TEMPERATURE COMPENSATION: Includes a temperature compensation device to ensure that measurement is easy and convenient. PRECISION MEASUREMENT: Adjustable eyepiece optical system: 4-8 times magnification system, stepless manual focus. Suitable for all eyesight. 4. HIGH QUALITY: Our chrome-plated brass body is resistant to chemical corrosion and wear, significantly increasing the lifespan of the refractometer compared to other aluminum housings.