NGK Spark Plugs offer the best in premium plug performance for stock or modified applications. NGK's IX Iridium Series Plugs were Designed Specifically for the Performance Enthusiast. NGK Fine Wire Center Electrode Ensures High Durability and a Consistently Stable Spark. Iridium Alloy has an Extremely High Melting Point, Perfect for Today's High-Tech, High Performance Engines. Trivalent Metal Plating Provides Superior Anti-Corrosion and Anti-Seizing Properties. Corrugated Ribs Prevent Flashover. Pure Alumina Silicate Ceramic Insulator, Provides Superior Strength and Better Heat Transfer. Copper Core Aids in Heat Removal. Triple Seals Prevent Leakage. All good qualities you can expect from NGK spark plugs. Beefcake Racing is an Authorized Dealer for NGK Spark Plugs, call 1-855-827-7223 for more inf.