The Genuine DENSO IRIDIUM POWER Spark Plugs 5357 IK16L are high-quality spark plugs designed for direct replacement in vehicles. Manufactured by DENSO in the United States, these spark plugs are engineered to provide reliable performance and long-lasting durability. With a manufacturer warranty of 1 year and a California Prop 65 Warning for nickel, these spark plugs are a trusted choice for car and truck owners looking to maintain optimal ignition systems and components. Upgrade your vehicle with this set of 4 genuine DENSO spark plugs for improved efficiency and spark plug reliability.