Oakton? Ecotestr TDS Low pocket meter features a large ergonomically designed display so that you can easily view measurements at a glance. The stainless steel electrodes are both rugged and chemical resistant, for use in a variety of applications. Other features include ATC (Automatic Temperature Compensation), hold function, it is completely waterproof and has a transparent plastic cap that can be used as a container for calibration or measurement purposes. Range: 0-1990 ppm, Resolution: 10 ppm, Accuracy: 1% full scale and Conversion Factor: 0.4 to 1.