This MSD 31239 Universal Super Conductor 8.5MM Spark Plug Wire Set is the ultimate performance wire for engines with late model HEI “spark plug top” distributor caps! This wire set comes with the spark plug terminal and boot installed, with the other end open. Distributor cap boots and terminals are included, so you can custom tailor the length of each wire. These wires use a helically wound copper alloy conductor with only 40-50 ohms resistance per foot of wire. Less resistance means more energy to the spark plug to ignite the air/fuel mixture! Each foot of finished wire features 40 feet of this conductor for high EMI suppression as well as superior conductivity! This highly effective “choke” keeps the Electro Magnetic Interference inside the wire as well as away from other electronics. This combination is encased in a heavy-duty sleeve that withstands abrasion as well as high temperatures. Stainless steel Dual Crimp snap lock terminals as well as high temperature boots ensure you have the best wire available! MSD 31239 Universal Super Conductor Spark Plug Wire Set Features: Wire Color: Red Spark Plug Boot Color: Gray Distributor Boot Color: Gray Diameter: 8.50mm Spark Plug Boot Ends: Eight 90 Degree Distributor Terminal Ends: Male/HEI and Female/Socket Spark Plug Boot Material: Silicone Distributor Boot Material: Silicone Conductor Style: Spiral Core Spark Plug Wire Resistance: 40-50 ohms/ft. RFI Suppression: Yes Coil Wire Included: Yes Clip-On Cylinder Markers Included: Yes Includes Mini Stripper-Crimper Assembled: No Quantity: Sold as a set From street cruisers to Top Fuel dragsters, MSD's ignition systems have been the industry leader for over 40 years without reservation. MSD continues to push the envelope with cutting-edge ignition technology as well as intake manifolds and EFI systems.