Adwa AD-12 pH meter waterproof - Has a resolution of 0.01 pH and 0.1 ° C. - An accuracy: 0.1 pH and 0.5 ° C. - With Automatic Temperature Compensation (ATC), so reliable results. - Has two benchmarks: pH 4.01 and pH 7.01. - A range of 0 - 14 pH and -5 ° C - 60 ° C - With temperature readout. - The electrode is replaceable. - Has auto shut-off and hold function. - The pH meter is very high and also favorably priced. - Furthermore, you thereby get 2 year warranty on the meter plus 6 months electrode.