HANNA electrode storage solution prepared with reagent grade chemicals that can be used to ensure optimum performance of your pH and ORP electrodes. Properly storing your pH or ORP electrode in a solution keeps the glass membrane well hydrated which maintains proper function and provides accurate readings.HANNA Storage Solution for Electrodes+ special formulation to minimize bacterial growth on your electrode+ clearly marked expiration date and lot number for traceability+ designed for storing any pH or ORP electrode+ regular maintenance of the electrode is crucial for its service life and the quality of the measurement results