CYCLOPS INSTRUMENTS Antifreeze Premium Refractometer for Automotive Antifreeze System, AdBlue, DEF, Battery Acid, and Windshield Washer Fluid | Measures Freezing Point Temperature and Concentration

The instructions were very poor. I had to refer back to the item description on Amazon to get the information I needed. Once I had the info it was easy to use the item. I found it very easy to use and extremely accurate. There are several scales for different liquids so this tool is very useful. The antifreeze scale is marked in centigrade so I had to convert the reading to Fahrenheit for my local use. It would be handy if the instructions included a conversion chart. This tool gives much better results than the tube wilt floating balls . It is nice to get a tool that works well and doesnt require batteries. Just point it at the daylight and it works. I like that they included a dropper for getting the sample from the radiator to the tool. Overall very good tool , poor instructions, good value. I would get this again.

The Cyclops Refractormeter comes in a hard plastic box with a squeeze bulb, cleaning cloth, small screwdriver, and instructions. The instructions needed improvement, the pictures didnt depict the scales as seen through on the eyepiece. It also references calibration of the device, it appears (to me) the device was already calibrated at the factory, using distilled water, it already indicated a zero reading, which is what you want. Turning the adjustment knob in either direction didnt affect the meters readings. I watched a Youtube video on how to use a refractometer. I was able to test the anti-freeze and windshield washer fluid in my car to confirm their freezing points, which it did. The scales were in Celsius, so I had to convert to Fahrenheit with my smartphone. Overall, a neat device that I probably wont use too often, maybe once/twice a year to check my anti-freeze/washer fluid if adequate to hand the cold for ski season. Rated 4-stars.

This instrument is relatively easy to use, and the instructions are well written but do not get into deep details. Calibration is easy, and that is the main focus of the instructions. Then, the optical scale grades battery fluid and liquids with an antifreeze agent. For battery fluid, the scale provides a density equivalent since that is the actual metric for characterizing the state of the battery. For antifreeze, the freezing temperature is the relevant value. I appreciate the large range of focus adjustment on this instrument, it accommodates people that depend on glasses with high dioptric values. I cannot tell how accurate the measurements are, I can tell that the measurements are consistent, which is a good proxy for the quality of the instrument. Much easier to use than regular density testers, just a drop of fluid is all it takes. The manual states that temperature plays a big role in accuracy, and fluids should get to room temperature for accurate readings. For the immediate practical value, this instrument confirmed my suspicion about a cheap windshield washing fluid bottle that I picked up on a road trip from the middle of nowhere a while back, and ever since I suspected it has only color and nothing else but water. I also did a test of battery fluid, mostly to test if the materials in this instrument withstand the acid solution: all good, got both a satisfactory measurement and also there was no fogging of the lens nor discolorations to the other parts of the instrument that may have come in contact with the fluid. I expect this will save me from some unnecessary fluid changes like engine coolant changes pushed by repair shops more often than the time or mileage based replacement schedule recommended by the car manufacturer, a waste of money if the fluid is clean and still within parameters. I just love being in the know when there is push for not-needed work on the car.

It says refractometer but it actually doesnt really give a refraction measurement. It just tells you what temperature range your liquids will freeze at. This is good for car maintenance, which is what it is designed for. Its pretty easy to use, just place the sample between the plastic slides and hold it up to the light. If you are having trouble seeing it through the eye piece just adjust the focus.