ACDelco 746SS GM Original Equipment Spark Plug Wire Set The same performance as your GM vehicles original factory component Spark plug distributor boot shape and materials provide proper fit, installation, and water-tight seal Terminal design improves spark plug retention and assists installation with excellent corrosion resistance Fiberglass braid and carbon impregnated fiberglass core for added strength and superior conductivity Engineered for electromagnetic interference and radio frequency interference (EMI/RFI) noise suppression SAE J23031 Class E wire rating to resist heat, cold, and electrical interference GM-recommended replacement part for your GM vehicle's original factory component Offering the quality, reliability, and durability of GM OE