Portable Copper-Sulfate Reference Electrodes by Fontana

Copper – Copper Sulfate Half Cell Reference Electrodes.
Made of the most DURABLE PLASTICS, the Half Cells will withstand severe abuse without damage. The pre-saturated ceramic plugs are of a special design for LOWER EARTH RESISTANCE contact and also allow for easy probing in hard earth.
These ceramic plugs provide a larger surface area than ever before.