Hanna Storage Solution Humidity Packs Simply squeeze the lever to Simply squeeze the lever to water and release the lever to stop watering while moving from one plant to the next DYNOMYCO C™ was designed and formulated by a team of biologists HI 70300L 500 ML Special formulation to minimize microbial growth and osmotic diffusion effects between the solution and inner reference electrolyte Clearly marked expiration date and lot number for traceability Designed for storing any pH or ORP electrode Properly storing your pH electrode in a solution keeps the glass membrane well hydrated which maintains proper function and provides accurate readings