Magnum Spark Plug Wires Red for Harley Davidson XL 04-06 High-voltage, high-temperature, 8mm silicone ignition wires featuring high-performance suppression conductor cores for compatibility with all H-D ignition systems Posi-Lock spring clip terminals and the highest quality silicone spark plug boots Tuned (ohm resistance) conductor core is engineered to duplicate OEM specifications for computer module compatibility to ensure maximum performance and clean spark delivery Heavy-walled extreme duty crystal clear Teflon outer insulation eliminates the need for grounding wires and ensures no interference with late model computer modules Each strand of the outer braid is coated with a plastic enamel and then covered with a clear Teflon skin