Portable auto refractometer Methanol Antifreeze Tester -50~0 Methanol Freezing Point meter Water freezing point tester RZ127 Please note:send without battery Other Refractometer for choice,As below: Refractometer Measuring Ranges Sugar refractometer RZ111 0~10% RZ112 0~20% RZ113 0~32% RZ114 0~50% RZ115 0~80% RZ116 0~90% RZ117 28~62% RZ118 45~82% Honey Baume meter RZ119 58~90% Salinity meter RZ120 0~100% Food salinity meter RZ121 0~28% Alcohol refractometer RZ122 0~80% Handheld Freezing Point meter RZ123 -50~0C 1.10~1.40 Urea freezing point meter RZ124 '-50~0C Urea:30%~35% Milk concentration meter RZ125 0~20% Soymilk concentration meter RZ126 0~25% Methanol Freezing Point meter RZ127 -50~0 Wine Refractometer RZ128 0~40% Beer malt refractometer RZ129 0~32% 2 in 1 Food salinity and suger Refractometer RZ130 0-28% Description: ATC accuracy: Hand held brewing refractometer with automatic temperature Compensation (ATC), the brix refractometer will account for changes in ambient temperature and automatically compensate accordingly to provide accurate and repeatable measurements on an easy to read scale. Dual scale -Measurement range -50~0C . 1.ATC: Built-in automatic temperature compensation 2. Dual design: Rapidly and precisely display the Measurement range (-50~0C ) , without switching units! Easy to use Simply test a drop of your brew on the prism and hold the refractometer to the light, then look through the eyepiece to get the reading, no need for clutter some tables! Operation steps 1. Open the cover with a soft cloth carefully wipe detection prism. 2. Test a few drops of the solution, placed on the detection prism, gently close the cover ,to avoid air bubbles, spreading the solution acro the surface of the prism. 3. Align the light source and observe through the eyepiece, adjusting with the wheel. 4. Make a clear dividing line between blue and white marks. Scale value is the concentration of the solution of the boundary. Calibration Method:(Details please check below photos ) Accurate measurement depends on careful calibration.To calibrate the refractometer accurately.First you should make sure the ambient temperature is about 68F,I recommend you do the calibration in an air conditioned room in which the temperature is set on 68F. Distilled water to calibrate Open the cover plate,place 2-3 drops of distilled water on the prism,then close the cover plate and make sure the water spreads acro the prism without air bubbles or dry spots.Waiting for about 30 seconds to let the reading to stabilize,look into the eyepiece and turn the calibration screw with the screw driver until the reading is "0". Packing list: 1*Refractometer 1*Clean Cloth 1*Screwdriver 1*Dropper 1*Instruction manual 1*Box or not