GroChek Combo pH EC TDS Meter is the new meter from Hanna Instruments combines 4 meters into one easy to use wall mounting continuous indicator. Featuring a large, dual-level, back-lit LCD display the meter can display the temperature of your solution together with the choice of either conductivity, pH or total dissolved solids (TDS). At startup this indicator performs a self-check to assure proper working condition. It also features a reading stability indicator and a hold feature to make it easier to write down a particular reading. Calibration and temperature compensation is automatic, while the conductivity and TDS conversion factors and temperature coefficients are user adjustable for specific application requirements.