High performance 8mm wire-wound supression core producing 300 ohms of resistance per foot. Up to 15 times more efficient than factory OEM wires to promote faster and more complete fuel burn in the cylinder head. Resists temperatures up to 600°F. Competition Sleeving (used by most Winston Cup teams), covers the entire length of wire, boot to boot, is silicone over fiberglass braid, provides 8000 volts of additional insulation to the wire and eliminates spark plug misfire and spark jump. Dyno tested, resulting in 2 - 6 hp increase over factory OEM wires. Highest quality silicone spark plug boots and coil boots. Posi-snap lock stainless steel spring clip terminals. Suppresses radio frequency interference that electronic ignition systems demand. Double insulated at spark plug and coil ends. Available in 8 custom colors: Gray, Blue,Purple, Red, Orange, Yellow, White, and Black. Available for H-D® and most aftermarket V-Twin applications (i.e. Fat Bastard®, Big Dog™, Bourget™, etc.). Wire sets come complete and ready for nstallation. Plug wires have chrome embossment of the Ultima® logo.