DEI Protect-A-Wire kits provide thermal protection for expensive spark plug wire sets. Protect your wires from potential burning, cracking, and hardening typically caused by severe under hood heat. DEI wire heat protection kits easily install by removing the distributor boot and sliding Protect-A-Wire(TM) over spark plug wire. Constructed from high temperature resistant glass fiber material Protects electrical wiring, speedometer cable, hoses & more 8mm ID Includes DEI Hi-Temp Boot Shrink Tubes 2 Cylinder Kit Contains: 7 feet of sleeving & 6 Hi-Temp Boot Shrink Tubes 4 Cylinder Kit Contains: 13 feet of sleeving & 12 Hi-Temp Boot Shrink Tubes 8 Cylinder Kit Contains: 25 feet of sleeving & 25 Hi-Temp Boot Shrink Tubes