WTW SenTix® 41 Low-Maintenance pH electrode with temperature sensorOverview WTW SenTix 41 pH probe for freshwater. pH electrodes with gel electrolyte and built in temperature sensor are ideal for portable measurement but also for routine measurement in the lab. PRODUCT FEATURES Standard electrodes with gel electrolyte and built in temperature sensor for pH measurement in lab and field. Maintenance free gel reference system over the entire product life Automatic temperature compensation Robust plastic shaft The new