8mm black silicone and synthetic jacketing resist heat,oil, and abrasion. 500ohm/ft resistance delivering greater spark energy, while improving power, idle and fuel efficiency. A combination Kevlar Helically Spiral Wound Core conductor for greater strength and durability that supresses Electro Magnetic and Radio Frequency Interference. Matching black silicone boots protect against high exhaust temperatures. Double spring locking terminals for secure vibration proof connections.