NGK 7159 TR55-1GP SPARK PLUG Direct replacement upgrade for superior performance with a 30,000 to 50,000 mile service life. Platinum wire center electrodes improve engine starting in harsh conditions, and provide faster starts and quicker acceleration. Best Platinum spark plug at an economical cost. Precision laser-welded electrode construction. Trivalent Metal Plating has superior anti-corrosion and anti-seizing properties.