These blue spark plug wires feature a silicone inner core and outer jacket that keeps the wires flexible while maintaining their color. The core consists of a high conductive resistor conductor spiral that provides more fire power and up to 10 times less resistance than standard resistor core wires. The wires eliminate radio frequency interference and are great for use with multi-spark discharge systems, electronic ignitions, and on board computer systems. They provide heat protection up to 600-degrees F, come with 180-degree plug boots, and fit 8-cylinder engines.