NGK (5077) ZGR5A Spark Plug - Pack of 4 Improved performance over OEM and Standard plugs for high performance operation with a 30,000 mile service life. Advanced V-groove design and high performance Nickel electrode enhances spark development. Economical performance plug for older vehicles. Precision laser-welded electrode construction. Trivalent Metal Plating has superior anti-corrosion and anti-seizing properties.