PREVENTS BURN-THROUGH & CRACKING – Shields spark plug boots and ignition wires from extreme under-hood temperatures to reduce misfires and costly repairs. EXTREME HEAT RESISTANCE – Made from high-temperature braided fiberglass, withstands continuous direct heat up to 1,200°F for reliable engine protection. NON-FLAMMABLE & FLUID-RESISTANT – Resists oil, water, and most automotive chemicals, ideal for high-performance, off-road, and daily driver applications. REINFORCED DOUBLE-WALL DESIGN – Durable dual-layer construction with built-in reinforcement ring for easier spark plug access and long-lasting protection. FLEXIBLE UNIVERSAL FIT – 1" internal diameter fits most straight or angled spark plug boots; installs quickly without trimming or tools. Made in the USA