Like optical probe tips, the optoelectric probe has an optical fiber of the specific NA and core diameter with M3 connector at one end while its loose end is much longer and suitably protected and strengthened to keep its direction. In addition, this probe has electrical wire that goes along the optical fiber, from near the tip to the groove in zirconia ferrule. 

Note: The electrode protrusion length is the distance in nm between the fiber tip and the electrode tip. Positive means the electrode is longer.