Fine-Wire Double Platinum features Platinum pad on both electrodes. Extended service intervals (on all except Nickel and Standard Copper Core plugs), Proprietary platinum pad on side wire electrode (on Platinum-Iridium and Fine-Wire Double Platinum plugs). Platinum-Iridium plugs feature Iridium-enhanced center electrode. Platinum-Iridium plugs can be used in any engine regardless of ignition system. High-Strength Steel High Thread spark plugs for 3-valve Triton engines redesigned: New, high-strength steel shell, Nickel-plated shell for corrosion resistance, Scavenger area allows for more carbon build-up before misfires occur, Full ground strap helps for better heat transfer within the combustion chamber, Thicker insulator for better misfire prevention.