Denso TT Nickel Twin Tip Spark Plug K20TT / 4604 Replaces FR51 PFR6E10DENSOs world-first patented Nickel TT Spark Plugs feature a nickel centre & twin 1.5mm diameter protruding ground electrode achieving superb ignition efficiency without expensive precious metals. Fuel efficiency Reduced Emissions Highly Consolidated Range Born for cold Starts DIMENSIONS: Height (mm): 43 Width (mm): 24.5 Length (mm): 85 If 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.