Protect your spark plug wires from melting on hot exhaust headers with this 8-pack of heavy-duty heat shield sleeves from Gearzaar. Made from basalt fiber, these things are seriously tough. They're rated for continuous use up to 1800°F and can handle intermittent spikes up to 2500°F. They have a double-wall construction to really reflect and dissipate heat. Each sleeve is about 15.2cm (6 inches) long and is stretchy enough to fit over most standard spark plug boots, even 90-degree angled ones. They slip right over your existing wires and boots. Part number NF-GRZ0001. If you've done engine mods, have tight engine bays, or just want to prevent premature wire failure, these are an inexpensive insurance policy. Comes with a manufacturer warranty. Keep your ignition system running cool and reliable.