0.01 pH resolution) - Totally Waterproof - Low Power Consumption - Automatice Switch-off - Low-battery Alarm (as long as there is any display, the accuracy is guaranteed) Model :PH-901 PH-901A PH-901B PH-902A PH-902A Measuring Range: 0.00 - 14.00 pH Accuracy :≤+/-0.03pH ≤+/-0.10pH ≤+/-0.03pH ≤+/-0.03pH ≤+/-0.10pH Calibration: 2 points Plug: fixed electrode fixed electrode BNC + 1 m cable replaceable electrode replaceable electrode Temp: 5 - 50掳C (ATC) Size: 150 x 22 x 20mm