Component of the exocyst complex involved in the docking of exocytic vesicles with fusion sites on the plasma membrane. The exocyst complex is composed of sec-3/exoc1, sec-5/exoc2, sec-6/exoc3, sec-8/exoc4, sec-10/exoc5, sec-15/exoc6, exo-70/exoc7 and exo-84/exoc8. Pseudocoelom. Belongs to the SEC8 family.