Upgrade your vehicle's performance with the X4XZ Ignition Coil and Iridium Spark Plug set, specifically designed for Cadillac, GMC, Chevy, and Buick models. The package includes six performance ignition coils and six iridium spark plugs, ensuring a significant 15% increase in performance and energy efficiency. Each component is engineered for precision and durability, backed by a lifetime manufacturer warranty. The coils are OE/OEM replacement parts, matching numbers 12618542, UF-569, GM12632479, 12610626, 41-109, UF569, and 12632479. The spark plugs feature a unique design for optimal combustion and are designed for front placement on the vehicle. NOTE!!! These are shipped in a flat rate mailer to save you on shipping. All items are brand new.