Optical winemaking tool that allows a quick and accurate measurement of the amount of sugar (Brix) in your grapes in the field, helping to determine optimum harvest time. Built out of metal, it offers a rubber grip, comfortable rubber eyepiece, focus adjustment, pipette, calibration screw, and a protective hard vinyl plastic carrying case. Complete instructions with diagrams included. The refractometers are equipped with superior optics, an easy-to-read display, and our 0-32 Brix model has an automatic temperature compensation system - no temperature conversions to worry about! Easy to use and lightweight. Calibrate with distilled water and a small screwdriver (included).