Sumax 409 Pro Race 10.4mm Spark Plug Wires For Harley Touring Features: These wires from Sumax feature the same spiro core as the colored 8mm wires but with a fat 10.4mm insulator cover These sets are ready to plug and run Placement of Wires: Front Lower Left Tower 3: 34 90 coil 135 plug, Rear Lower Left Tower 4: 18 90 coil 135 plug, Front Center Cylinder Tower 2: 30.5 90 coil PC plug, Rear Center Cylinder Tower 1: 17.25 90 coil PC plug