NGK Coil over Plug Boot is designed to precisely control the spark intensity timing for optimum power and low emission. It is constructed with durable material that is corrosion and abrasion resistant. This can be installed easily and ensures longevity and durability. You can depend on NGK for quality and reliability. Constructed with durable material. Corrosion and abrasion resistant. Control module is located away from engine heat. Ensures durability and longevity.