Technical parameters Model PHB-2000 Measuring Range-2.00pH 18.00pH -1999mV 1250mV -10.0 199.9 Resolution 0.01pH, 1mV, 0.1 Accuracy of + / - 0.01 pH + /-1digit + / - 1 mV + / - 0.1 + /-1digit Temperature Compensation Automatically or manually 0.0 99.9 Recognized standard solution 4.00 / 7.00 / 10.01 pH 4.01 / 6.86 / 9.18 pH 9V Power Adapter The voices of all the keys Appearance 180mm X 110mm X 50mm Weight 0.25 Kg