By utilizing an advanced microprocessor, HI 9023 is able to perform pH, ORP, ISE and temperature measurements for a long period of time without the need for frequent battery changes. mV measurements automatically switch from 0.1 to 1mV resolution when the reading reaches 400mV. Temperature effects are automatically compensated for, from 0 to 100C (32 to 212F) or can be manually compensated for, on the control panel in the same range. The meter has three memorized buffer values, (pH 4.01, 7.01, 10.01) and automatic buffer recognition to avoid errors during calibration. There are no trimmers, making calibration an easy process, even for non-technical personnel. If you prefer to have only one probe for both pH and temperature, then place your order for HI 9023CN. It is supplied complete with the 4-in-1, plastic-body, gel filled HI 1217D pH/C electrode with built-in temperature sensor and amplifier in a rugged carrying case.