'Fired in' resistor for stable resistance value and smoother running engine Zero-leakage seal encloses hot, high pressure combustion gases Durable nickel finish offers wear and corrosion resistance Ceramic insulator provides high performance in severe operational conditions Reduced fouling and enhanced heat range control High Conductivity Copper Core Center Electrode Proprietary Glass Center Seal High Alumina Ceramic Insulator Nickel Finish Nickel Ground Electrodes Vacuum Infused Center Electrode Hot-Lock Assembly Harness Wire Contact