The HI96769C Anionic Surfactant Portable Photometer combines accuracy and ease of use in an ergonomic, portable design. A user can accurately determine the concentration of anionic surfactants as SDBS within a 0.00 to 3.50 mg/L (ppm) range using the HI95769-01 ready made reagents. The HI96769C offers many advanced features including the exclusive CAL Check™function used for performance verification and calibration of the meter.