These Moroso Mag-Tune spark plug wires are fully tested to ensure secure termination, electrical conductivity, and dielectric strength. They feature moisture-resistant 100 percent silicone boots and snap-lock spark plug terminals. The Moroso Mag-Tune spark plug wires start with a conductive latex-coated, heavy-duty fiberglass core and then add a spiral-wound stainless nickel alloy conductor over the top. Added to that is a fiberglass reinforcing braid, and they finish the construction with a high-temperature EPDM jacketing.