PH-099, designed for simultaneous pH and ORP measurements. It also reads temperature, which is continuously displayed on the dual level LCD. It is a waterproof pH, ORP and temperature meter. All pH readings are automatically temperature compensated(ATC). Measurements are highly accurate with a unique stability indicator right on the LCD. The pH electrode, supplied with the meter, is interchangeable and can be easily replaced by the user. Range : mV 0~1999mV pH : 0.00 to 14.00 pH Temperature : 0 to 55 Resolution : mV 1 mV pH : 0.01 pH Temperature : 0.1 Accuracy : mV 5mV pH : 0.1 pH Temperature : 1 Temperature Compensation : 0 to 50 Electrode : replaceable pH electrode (included);fixed ORP sensor Power Supply : 4 x 1.5V(AG13) Environment : 0 to 50 Dimensions : 170 x 40 x 23 mm Weight : 100 g.