Kit Content:6 x Denso COP Direct Ignition Coils6 x NGK Iridium IX Spark PlugsItem Description:Thread Diameter(mm): (Spark Plugs) 12.00Center Electrode Core Material: (Spark Plugs) CopperCenter Electrode Tip Material: (Spark Plugs) IridiumGround Electrode Quantity: (Spark Plugs) 1Electrical Terminal Type: (Spark Plugs) Non-Removable NutColor: (Direct Ignition Coils) GraySeat Type: (Spark Plugs) FlatGround Electrode Tip Design: (Spark Plugs) Taper CutManufacturer Heat Range: (Spark Plugs) 7Resistance(Ohms): (Spark Plugs) 5000Pre-Gap Size(in): (Spark Plugs) .044Hex Size(in): (Spark Plugs) 5/8Ground Electrode Core Material: (Spark Plugs) NickelReach(mm): (Spark Plugs) 26.5Voltage(VDC): (Direct Ignition Coils) 12Ground Configuration: (Spark Plugs) StandardInsulator Height(mm): (Spark Plugs) 51.00