This is a set of "MSD 8.5mm Spark Plug Wires" for a 1986 or 1987 Buick Grand National, T Type, Turbo T, or GNX 3.8 liter turbo V6. 8.5mm Super Conductor wire sets have a special helically wound core that has just 40-50 ohms of resistance per foot--but with an RFI suppression equal to a 1,500 ohm wire. In fact, each foot of finished wire features 40 ft. of tightly wound copper for superior conductivity. A tough, 8.5mm synthetic/silicone jacket over an extra-heavy glass braid and dielectric insulator keeps the current guided to the plugs. Underneath the high-temperature boots, dual crimp stainless steel terminals feature snap-locks to ensure a secure fit. MSD's 8.5mm Super Conductor wire sets have protection up to 600 degrees Fahrenheit and 102,000 volts dielectric strength, a must for the extreme conditions of open wheel racing and under hood temperatures.