Make sure you reference your owner’s manual BEFORE ordering car parts. THIS ITEM IS NON-RETURNABLE. - Set of 4 spark plugs - NGK Honda Genuine Parts, Made in Japan - For most Honda petrol vehicles (Please check part number: DIFR6D13 ) - NGK 0.4mm Iridium spark plugs feature an ultra-fine center electrode (0.4mm) that’s designed just thick enough to ensure the maximum durability and life of the spark plugs-and just thin enough to create an accurate and consistent spark - They represent the ultimate evolution of spark plug technology and performance - Iridium is the hardest metal used in spark plugs today-six times harder than platinum. This allows for reduced voltage requirement for a spark - Lower fuel consumption - Longer engine life - Smoother engine running - Improved ignition efficiency giving enhanced power and acceleration