Water-resistant Low Power Consumption Automatice Switch-off Low-battery Alarm (as long as there is any display the accuracy is guaranteed) Model: ZTS-CF ZTS-EC ZTS-TDS ZTS-uS/cm ZTS-mS/cm ZTS-ppm ZTS-ppt Measuring Range: 0-100 CF 0-19.99 EC 0 -1999 mg/l 0-1999 uS/cm 0-19.99 mS/cm 0-1999 ppm 0-10.00 ppt Resolution: 1 CF 0.01 EC 1 mg/l 1 uS/cm 0.01 mS/cm 1 ppm 0.01 ppt Accuracy:+/-2% FS Temp: 5 - 50癈 (ATC) Size; 150 x 32 x 16 mm