Denso Spark Plug Denso's standard plugs have always offered a patented U-groove ground electrode producing for a larger, hotter spark. Copper core for better thermal conductivity. Machine rolled threads to reduce cross-threading and seizing . The plug insulator is constructed of purified alumina powder for extreme stress with 5 ribs to prevent flashover.

Product Features:

• U-Groove Ground Electrode Promotes Ignitability and Decreases Quenching
• Fully Projected Insulator Reduces Carbon Fouling
• Machine Rolled Threads Prevent Seizing or Cross Threading During Installation and Removal
• 100% Pre-Fired to Assure the Highest Quality Possible
• Purified Alumina Powder Insulator Provides Exceptional Strength and Thermal Conductivity
• Five Rib Insulator Prevents Flashover
• Copper-Glass Seal Bonds Center Electrode and Insulator for a Gas-Tight Seal