Apera Instruments, AI3133, LabSen 333 Professional 3-in-1 pH/Temp. Electrode for Wastewater TreatmentBacked by proprietary Swiss pH sensor technology and materials, the LabSen 333 3-in-1 pH/Temp. Electrode is temperature compensated pH electrode, and is designed for testing wastewater, emulsion, suspension, and samples containing protein and sulfide (This is a replacement probe for Apera Instruments SX811-WW Meter).LabSen unique blue hemispherical glass membrane- faster response time, better repeatability, and built tough, highly resistant to general impact (totally differentiates from the fragile conventional glass bulb membrane).Long-Life Reference System- The LabSen 333 pH electrode adopts a long-life reference system, which is composed of a glass tube, AgCl and a reference silver wire. The top end of the slim glass tube is stuffed with cotton, which prevents the reaction between AgCl and electrolyte when temperature changes. It improves the stability of reference electrode and prolong the service life of the electrode.Polymer Electrolyte- The solid polymer electrolyte is in direct contact with test samples. The anti-pressure capacity can reach up to 6 bars, making it ideal for testing suspension and wastewater. No more frustrating clogged junctions.Compatible with Apera Instruments' meters such as PH700, SX823-B, MP511,PH800, PC800. May NOT work with other brands' meters because the temperature unit might be incompatibleFeatures:Unique LabSen blue glass membrane from Switzerland, faster response rate, better repeatability, and impact-resistantPolymer Electrolyte, ideal for testing wastewater and suspension. No more clogged junction.Long-Life Reference System, improving the stability of reference electrode and prolong the service life of the electrodePOM housing, highly resistant to corrosions.