Slope pH electrode ± 30% at pH 4.00, 4.01, 9.18, and 10.01 > 1012 Ω input resistance Technical Specification for Digital pH Meter PCE-PH 23: Temperature measurement Measuring range temperature 0.0 ... 99.9°C / 32 ... 211.8°F Resolution temperature 0.1°C / 0.18°F Measuring accuracy temperature ±...