Denso Iridium Extended Spark Plug SKJ20DR-M13 / 3401 Replace IZFR6K13The material Iridium is far superior to platinum, and is actually extracted from meteorites. The metal is 6 times harder, 8 times stronger, and able to take temperatures up to 1200ºF hotter! The DENSO Iridium center electrode tip is the world\'s smallest (only 0.4mm diameter) to produce the hottest most concentrated spark, while requiring the least voltage (5,000 less volts to fire than conventional spark plugs!) For performance or everyday driving, this plug is the one!Low required voltage Better acceleration response and operational stability Lower fuel consumption Longer lifetimeDIMENSIONS: Height (mm): 44 Width (mm): 24.5 Length (mm): 85If you are unsure as to whether this is the correct part for your vehicle, please don\'t hesitate to contact us. Alternatively please use the cross reference table above.