This Abbe refractometer is ideally suited for measuring the refractive index of glass as well as other transparent and translucent liquids and solids. The instrument can be configured to work in either the traditional “Transmitted mode” or, for non-homogenous or opaque samples, “Reflected mode”. The prism is illuminated by aligning the reflector with a suitable light source, the borderline may then be observed through the eyepiece and a reading can then be taken from the combined refractive index or Brix scales. Accurate regulation of the prism temperature is achieved via the waterbath connections and can be monitored via the integral digital display (Temperature display in Centigrade only). Readings may be obtained to 4 decimal places on the refractive index scale and 1 decimal place on the Brix scale. The included contact liquid can be used with samples up to 1.65 RI, when testing samples with a refractive index greater than 1.65, #59-580 is also required. Model includes: glass calibration plate, contact liquid (for samples up to 1.65 RI) and instruction manual. Also included is a hard flight case for easy transportation and storage.