ACDelco 41-979 Professional Platinum Spark Plug (Pack of 1) One-piece, fired-in suppressor seal blends three glass types for a gas-tight seal that helps reduce radio frequency and engine interference, regulate spark plug energy, and protect against compression pressures for long life Double platinum point pad on center and ground electrode offer excellent durability and consistent voltage demands to help reduce wear on ignition system Pure copper core results in cooler electrode temperature for maximized durability and fouling resistance