Improve Your Fuel Efficiency and Horsepower with Performance Products Engineered Spark Plug Ignition Wire Sets By Karlyn/STI Our European wire sets are made with the finest copper core silicone wire which greatly exceeds O.E. and competitor specifications. This double extruded Silicone-over-Silicone wire contains 19 strands of tinned copper core which provides "super conductivity" with superior corrosion resistance. Our wire sets always include O.E. Type Connectors, Looms, Sensors, and Harness Clips &Heat/Abrasion Shields whenever needed. This results in a state-of-the-art wire set.