Wetting Front Detectors are funnel-shaped instruments buried in the soil. As irrigation water infiltrates into the root zone, the Detector captures a water sample which can be used to measure nutrient and salt levels in the soil.
More information can be found at the FullStop Wetting Front Detector product description
One box contains:
2 × Complete FullStop Wetting Front Detectors
2 × 280g bags with filter sand