Features: Widely used as a solution for your burning for spark plug wires. These universal for spark plug wire caps provide good thermal for protection for spark plug wires, especially on engines with excessive exhaust fittings. Works well with 90 degree, 45 degree and straight spark plugs. Fits most hot rods and classic engines. Also fits most angled and straight boots. Length is about 15.5 for cm long. Made of fiberglass material. The thick material is long enough to protect the for spark plug wire as it is close to the connector or exhaust manifold, helping to prolong the life of the wire as long as you keep the vehicle maintaining maximum spark. Easy to insert boot heaters into each boot of the for spark plug wire. Just slip the big end (the stitch) over the boot. Then carefully slide the ring end into the boot that attaches to the for spark plug. Made of fiberglass, can hold up to 1200 degrees Fahrenheit, double-layer construction for added durability. Specifications: Material: Ordinary Fiber Size: Approx.15.5x3.5x2.5cm/6.1x1.37x0.98inch Color: Black/Red/Blue Package Includes: 8x for Spark Plug Wire Sheath note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thanks for your understandings.