Environmental Express Oakton PCTSTestr 50 Pocket pH/Cond/TDS/Salinity Waterproof Tester, Premium 50 Series Ideal for water, wastewater, laboratory or plant use, this multiparameter tester features a long-life pH electrode with a wide range of sample compatibility. Pin-style conductivity sensor features stainless steel electrode for chemical resistance and durability. Replaceable sensor module saves you money by reusing the meter body. This tester brings the performance of your lab instruments out into the field. Advanced features include auto-shutoff, user-adjustable temperature coefficient, self-adjusting TDS and salinity factor, and low-battery indicator. Combine measurement capabilities of three testers in one convenient pocket-sized unitUp to 3 point pH calibration with NIST or USA auto buffer recognitionConductivity, TDS, and salinity feature auto ranging based on the concentration of your sampleLeakproof cap functions as a sample/calibration cup, hydrating cup, and stabilizing base to stand the meter upright Item number 35634-35 includes protective storage case, lanyard, and batteries Specifications Display LCD Min/Max pH -1/15 pH Resolution/Accuracy 0.01/±0.01 Buffer Recognition USA 4.01, 7.00, 10.01 and NIST 4.01, 6.86, 9.18 Calibration Up to 3 points Min/Max Conductivity 0 µS/20 mS Conductivity Accuracy ±1% full scale Min/Max TDS 0 ppm/10.0 ppt TDS Resolution 10 ppt Min/Max Salinity 0.00 ppt/10.0 ppt Salinity Resolution 0.01 ppt Salinity Accuracy +/- 1% FS Min/Max Temperature (° C) 0/60 Min/Max Temperature (° F) 32/140 Temperature Resolution 0.1° C / 0.1° F Temperature Accuracy 0°C to 50°C (±0.5°C / ±0.9°F ); from 50°C to 60°C (±1.0°C / ±1.8 °F )