Resists temperatures up to 600 degrees! Spiro-Pro Wire sets are for racing or street applications and provide maximum firepower without radio interference. These wire sets provide up to ten times the conductivity of standard resistor wires. Spiro-Pro Wire sets are manufactured from 100%, virgin silicone jacket over 100%, virgin silicone core. It stays flexible and retains it's original strength when other wire sets self destruct from heat fatigue. Due to it's density and flexibility, Taylor pure silicone has the highest dielectric strength of all materials used in ignition wires. Spiro-Pro Silicone Wire sets are available in bright red, white, blue, yellow, purple and teal. Spiro-Pro Wire sets can be used with standard or high performance ignition and are a must for HEI and Fuel Injection applications.