Our best selling Standard Abbe Refractometer measures the refractive indices nd and mean dispersion (nF-nC) of glass, as well as other transparent and translucent liquids and solids. Circulator nozzles allow the instrument to be attached to a circulating bath to allow for accurate temperature control of primary and secondary prisms. Dispersion correction is viewed through the eyepiece, while the refractive index is read from a 25 x 30mm projection view window. Includes shielded thermometer, calibration specimen, index-matching fluid (naphthalene bromide), screwdriver, and instruction manual. Unit features an on/off switch for LED, a switch to toggle between 110V and 220V and a removable power cable (US plug included out of box).