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

This enables you to buy a higher grade antifreeze and then add water to get it down to the level you want. I learned this trick from our Boat club yard manager. They buy -200 antifreeze and then water it down to the level they want. Good utility for this and a reasonable price.

Comes with the unit, a dropper, and instructions on how to use. Instructions were kind of hidden behind the padding inside the case, but they describe the procedure of how to calibrate and use it. It works well, though the calibration screw was a bit tight. They case is decent - a basic plastic case with some padding to keep it secure.

This tester will check battery acid, DEF fluid, Windshield washer fluid as both Propylene and Ethylene Glycol based antifreeze. Very good instructions

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.

Im sick of my old Preston bulb tester as its a piece of garbage. This refractometer will give you a dead nuts answer on the effectiveness of the coolant. I used these at a former place I worked at so I do have some knowledge on how to use it. Watch a video online on how it works as the instructions they provide are not that informative. Regardless, it seems to be providing accurate results.

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.

Im really impressed with the refractometer kit! It comes with clear instructions for calibration and use, a dropper for putting liquids to be tested onto the glass plate, a screwdriver for calibration, and a hard-sided case to keep this precision instrument safe amidst my other tools. Ive used it to check my antifreeze, which was very helpful. It also allows for testing of battery acid and washer fluid. The one note I would make is it was not clear exactly where the calibration screw is from the directions. Remove the rubber cap to reveal the hole where the calibration screw is, then turn the screw for calibration as clearly described in the instructions. Hope that helps!

Very Accurate instrument but must be initially calibrated. Delivers a more precise analysis of antifreeze condition and quality. A great value!

This is an excellent way to ensure your coolant and windshield wiper fluid have enough antifreeze. Without a proper level your engine may overheat, your engine block may crack or a wiper fluid reservoir could crack. It can also be used to test battery electrolyte health. I first tested some distilled water and found it to test out right at the waterline with no additional calibration required. As others have indicated, this can be a bit finicky to use until you get the hang of it. While my distilled water reading was very easy, my first attempt at Honda coolant was more difficult. The Honda coolant had no distinct results line until I gave the tester some vertical inclination and the line clearly popped showing -40 degree Fahrenheit (had to convert from Celsius). You may want to visually examine your coolant or wiper fluid before testing to ensure it looks normal as contaminants in it would skew the accuracy of the refractometer (e.g. wiper fluid created with hard water rather than distilled water, oil contamination in coolant). A nice tool at a low price. While I wont use this every time I buy coolant Ill be sure to use it if I do a brand swap or if I am concerned antifreeze protection is waning.

Still working of figuring out all the ins & outs of using a refractometer, but so far its been pretty cool.