Bluelab Bluelab pH Probe - pH Probe (Electrode or Sensor) for Measuring pH Levels in Nutrient Solutions and Soil Solutions - Accurate pH Measurements for use in hydroponics and Growing Systems

Size:1-Pack Easy to clean because of its bullet shaped glass bulb. Fully waterproof and less fragile than all-glass electrodes because of its tough polypropylene barrel. Gel filled (non-refillable) making it maintenance free and a double junction reference providing longer life.