This sodium chloride refractometer is a waterproof device and determines the percentage of sodium chloride in water with a measurement range of 0 to 28.5 %. You can visualize the measurement value and temperature of the sample on the LCD screen. Sodium chloride refractometer can measure different parameters, such as sodium chloride (%NaCl) and the refractive index, quickly and accurately with only four or five drops of the sample.