The Milwaukee MA884-BOX is a digital refractometer (optical instrument) that is based on the measurement of the refractive index of a solution, measuring %Brix and Potential Alcohol (% vol), and includes a protective hardshell case. The measurement of refractive index is simple and quick and provides the vintner an accepted method for sugar content analysis. Samples are measured after a simple user calibration with deionized or distilled water. Within seconds the instrument measures the refractive index of the grape. This digital refractometer eliminates the uncertainty associated with mechanical refractometers and is easily portable for measurements in the field. The instrument utilizes internationally recognized references for unit conversion and temperature compensation. Temperature (in °C or °F) is displayed simultaneously with the measurement on the large dual level display along with icons for Low Power and other helpful message codes.