C 102 is a portable turbidity meter or nephelometer specially designed for water quality measurements. The instrument is based on a state-of-the-art optical system that guarantees accurate results, assures long-term stability, and minimizes stray light and color interference. Periodic calibration with the supplied standards compensates for any variations in intensity of the LED light source. The 25 mm round cuvettes composed of special optical glass guarantee the repeatability of turbidity measurements.