NGK Spark Plugs - #3672 - LFR6A11 - Sold Individually. Keep ignition performance consistent with the NGK LFR6A11 standard spark plug. Chosen by more automotive, motorcycle, and marine engine manufacturers than any other, NGK standard plugs are built around a proven copper core and precision electrode design that support fast starts, dependable combustion, and long service life.. This plug is designed to hold up in real-world use, with features that help prevent leakage, resist flashover, and pro