Laboratory-grade performance in the field - The 2100P Portable Turbidimeter combines microprocessor- controlled operation and Hach's patented Ratio(TM) optics to bring greater accuracy sensitivity and reliability to field turbidity testing. The turbidity meter's two-detector optical system compensates for color in the sample light fluctuation and stray light allowing analysts to achieve laboratory-grade performance on a wide range of samples under a wide range of conditions.