If you're running headers with close tolerances or have an engine bay with little room, these ceramic ignition lead wire sets are the cure for burnt and melting boots. Their ceramic coating acts as a heat mirror, reflecting infrared energy and heat away from the plug boot, and it's engineered to resist flaking and peeling. The 8 mm spiral core silicone wires deliver maximum energy to the spark plugs with built in RFI suppression for your street-driven vehicle. 500 Ohm per foot resistance.