Accurate direct pH measurements in any substrate in seconds *Reinforced spear-tip for fast, direct measurement in substrates *Effective in soil, coco coir blends, rockwool, potting mixes and solution *Double-junction probe reduces reference contamination, extending longevity *Fast sensor response for quick and accurate measurements *Suitable for use with the Bluelab Combo Meter, Bluelab Combo Meter Plus and Bluelab Multimedia pH Meter *BNC connector is covered to prevent corrosion Our advanced probe technology ensures that you get lightning-fast pH measurements direct from the root zone or in solutions.