828M Champion Marine Spark Plug. Part# QL77JC4

Cut back ground electrode for small block Chevy, Ford and select marine applications. The ground electrode is cut back from the center electrode 0.40". The ground electrode face is concave around the center electrode to provide a constant gap. Constructed with a nickel shell for faster heat dissipation and copper core or double copper (when noted) for further heat removal, all are non-resistor except where noted with special Q-type resistor.