Bosch 9600 Double Iridium Spark Plug, Up to 4X Longer Life (Pack of 1) Did You Know? Bosch invented the first spark plug in 1902; with more than 115 years of continuous innovation, Bosch has produced over 11 billion spark plugs while developing over 20,000 types 4X longer service life than standard copper plugs, saving you time and money in the long-run .6mm fine wire reduces voltage requirement up to 24% for better combustion, lower emissions, increased fuel economy, and more horsepower Better ignitability and durability in cold weather while helping eliminate fouling Pre-set gap and nickel plated, rolled threads ensure a quick installation with no need to apply anti-seize