ISO-80P is a high impedance probe that can be plugged into the PROBE INPUT socket of the ISO-80. Insert the electrodes that will connect with the preparation/subject under test into the two sockets—one red, one black—on the probe. The probe headstage is epoxy encapsulated within a miniature gold plated metal case. The use of a probe, close to a recording site, minimizes the shunt capacity normally associated with long wire leads from the electrode to the amplifier.