1.Gem Refractometer: 2.CZ Testing Table 3.Stainless Steel 4.Monochromatic LED Lights 5.Dual power supply Gem RefractometerGemological refractometer,gem refractometer,gemological testerHigh hardness CZ test prism Scale range:1.35-1.81Error: ±0.002 Stainless steel table,easy to cleanBy advanced optic system,shadow edge is straight and sharp,easy to read.There are two ways of inputing the voltage: ...