Oyster™ meter with mini pH electrode and Polymer conductivity cell The Extech 341350A-P is a pH/Conductivity/TDS/ORP/Salinity meter with a large LCD built into the adjustable flip-up cover which is ideal for lab or field use. Microprocessor based with splash proof housing and front panel tactile touch pad for slope and calibration adjustments. Memory stores and recalls 25 readings. Featuring Automatic Temperature Compensation (ATC) for Conductivity/TDS and manual temperature Compensation for pH.