If you ever take a class that covers cooling systems,the instructors may mention that a refractrometer is the most accurate method of measuring the freezing point of a antifreeze solution. You place a drop under the slide and look through the ajustable viewfinder. The coolant reading is a dark band across the easy to read scale. We have tested several different manufactures and this little unit has the best optics. Don't worry about impressing your customers, impress yourself with your attention to important fundamentals.
We also supply this identical unit under the original manufacture's label, Leitenberger. No choice on labels, we ship what is in stock.