Description: Measuring Parameters: Range - pH , Accuracy - ± 0.07 pH ( pH 5 - pH 9 ), ± 0.1 pH ( pH 4 - pH 10 ), ± 0.2 pH ( pH 1 - pH 3.9, pH 10.1 - pH 13 ) , Resolution: 0 to 14 pH x 0.01 pH Display: LCD, size : 45 mm x 29 mm , Input Impedance: 10^12 ohms , Sampling Time : Approx. 0.4 second Operating Temperature: 0°C to 50°C , Operating Humidity: 80% RH , Calibration VR: External pH 4 ( slope adj. ) and pH 7 ( Cal. adj. ) calibration adjustment VR Power Supply: 006P DC 9V battery , Power Consumption: Approx. 2.0 mA Accessories: Instruction Manual , Optional Accessories: Electrode available