Dissolved Oxygen Meter, Dissolved Oxygen Range 0 to 20 ppm, Oxygen Concentration 1 to 200 Percent, Waterproof IP67, Displayed Temperature Range -6 Degrees to 46 Degrees C, 21.2 Degrees to 114.8 Degrees F, Salinity Range 0 to 40 ppt, Operating Temp. Range (F) 0 Degrees to 50 Degrees C, Operating Temp. Range (C) 32 Degrees to 122 Degrees F, Display Graphic, Auto Power Off Yes, Memory 50 Data Sets, Calibration Back Up, Cable Length 1 m, Power Source 9V Battery