DM-2: Commercial In-Line Dual TDS Monitor Install on industrial systems such as car washes, window washing, manufacturing, and food processing. FEATURES Highly efficient and accurate due to its advanced microprocessor technology. Displays TDS levels of the Feed Water and Product Water with in & out electrode probes. Auto-Off function conserves battery power. The unit shuts off automatically after 20 seconds. Dual Range - Measures from 0-999 ppm, with a resolution of 1 ppm. From 1000 to 9990 ppm, the resolution is in 10 ppm increments, indicated by a blinking 'x10' image. Factory Calibrated: our meters are calibrated with a 342 ppm NaCl solution. Meters can be recalibrated with a mini-screwdriver. Comes equipped with 1/4 inch Mur-lok® Quick-Connect T-fittings. Also available with 3/8" or 1/2" fittings. Installs quickly and easily.