... 3.Refractive index Measuring range(nD):1.3000-1.7000 4.22OV, A & E Lab. Main Products: Atomic Absorption ... , Turbidity Meter, Colorimeter, Gloss Meter, Tintometer, Automatic Polarimeter, Auto Melting Point Apparatus, Automatic Refractometer, Abbe Refractometer, PH/DDS/TDS ... device operation and acquisition;² External USB and RS232 ports can be directly connected to PC; USB disk and SD card interfaces ...