JBL Proflora pH-Sensor + Cal is a high quality electrode for pH value measuring. This probe can be connected to th JBL Proflora pH Control unit or all other pH value measuring and regulating systems with BNC connector. The electrode is filled with gel and very sturdy. The kit contains all necessary fluids for calibrating, cleaning and storage of a pH sensor. The pH electrode should be cleaned and calibrated regularly, this increases the life time significantly.