want a kind of professional heat insulator sleeve for your car spark plug? want to keep your car cable cooler? This can be your . Really practical and useful, just install it onto your car. Features -Color:Black -Material:Fiber glass -Size:15.50X3.50X2.50cm/6.09X1.38X0.98in - Helps prevent burns, hardening and cracking of spark plugs. Improve engine performance and extend the life of wires and plugs. - A spark plug heater protector for starters and wires that protects the performance and life of your plug and cord set. - The spark plug boot is made of two layers of fiberglass. Has good high temperature resistance and corrosion resistance. - Keep your car engine cool in summer, fits most modified engines. - The big end needs to be put over the boot. Then carefully slide the ring end into the boot that attaches to the spark plug. The other end is covered with a metal ring for easy installation. Package list: 8 x Spark Plug Boots