The Extech RF12 is a portable Brix refractometer and measures the concentration of lubricants and cutting fluids. Compact and easy to use, it requires only 2 to 3 drops of solution and provides accurate and repeatable measurements on an easy-to-read scale. The RF12 features a prism and lens with easy focus adjustment and automatic temperature compensation (ATC) from 10 °C to 30 °C.