Check the listing for details. Milwaukee EC40 EC/TDS Nutrient Meter for Hydroponics, Agriculture. Condition: New. Listed at 101.95 USD. The Milwaukee EC40 EC/TDS Nutrient Meter is designed for Hydroponics, horticulture and agriculture to help you make sure that your vegetables and plants are receiving the right amount of nutrient to promote healthy growth with low to zero product waste. Keep EC/TDS in your target range to help your achieve better results. Measures conductivity (EC) and total dissolved solids (TDS) with automatic temperature compensation. Ideal range for Hydroponics (0.2 to 4 mS/cm ' 2 to 40 CF ' 140 to 2800 ppm 0.7 scale ' 100 to 2000 ppm 0.5 scale). Units directly in mS/cm/CF/PPM (no conversions required). Factory calibrated no continious calibration required. EC/TDS electrodes can develop nutrient build up over time. To miminize build up, always rinse the probe in fresh tap or DI water after every use. High accuracy. Automatic Temperature Compensation (ATC). Auto on/off feature. Blue LED display. Graphite electrode in ABC + PC body. Battery level indicators. Battery life up to 3 years with approx. 10 measurements per day, 3 X 1.5V AA (batteries included).