【3500°F Heat Protection for Gas Engines】Dual-layer fiberglass construction withstands 1300–2000°F continuous heat and up to 3500°F peak. Designed to protect spark plug wire boots from extreme temperatures near headers, manifolds, and turbo components. Suitable for modified vehicles, towing, work trucks, and daily drivers. 【Prevents Burnout and Extends Ignition Life】Shields ignition wires and coil boots from heat damage, cracking, or melting. Helps maintain stable engine performance by protecting spark plug boots in high-temp conditions. 【Compatible with Most Boot Angles and V8 Engines】Each 6 inch sleeve with 1.4 inch inner diameter fits 90°, 45°, and straight spark plug boots, including thicker aftermarket wire sets and coil-on-plug setups. Works with LS, SBC, BBC, 350 454 gas engines. (Not for diesel glow plugs.) 【Tool Free Installation】Flexible and expandable fiberglass sleeves slide over spark plug boots easily—no tools required. Installs in minutes to deliver long-lasting heat and abrasion resistance. 【8 Pack Full Engine Coverage】Includes 8 spark plug wire boot heat shields for complete V8 coverage. Resistant to oil, fluids, abrasion, and corrosion. Ideal for cars, trucks, SUVs, and performance builds. (Wear gloves when handling fiberglass.) Upgrade your ignition system protection with this premium 8-pack spark plug heat shield sleeve set, designed for drivers who want better performance, better durability, and better value. Made with dual-layer fiberglass and reinforced for high-temperature resistance, these sleeves act as a reliable barrier against extreme exhaust and engine bay heat—preventing misfires, cracked boots, and premature wire failure. With an oversized 1.4" inner diameter and flexible construction, they fit most factory and aftermarket ignition setups, including thick plug wires, performance spark plug boots, and even upgraded spark plug wire separators. Whether you're running headers, a turbo engine, or a high-mileage vehicle, these sleeves help maintain cleaner ignition signals and extend the lifespan of your spark plug boots. Perfect for LS engines, classic V8 builds, hot rods, performance cars, trucks, and daily drivers, this set provides reliable protection at an affordable price point.