MSD Super Conductor spark plug wires transfer spark energy with the lowest losses possible while generating the least amount of radio frequency (RF) interference. They combine a much thicker copper alloy center conductor, helically-wrapped around a ferro-magnetically impregnated center core. This assembly not only lowers resistance to about 40-50 ohms per foot, but provides radio interference suppression equal to that of convential wire with around 1,500 ohms per foot of resistance.