Manufactured to OEM quality standards. Product Features:No-compromise, top of the line race spark plug for the most serious enthusiast.Patented U-groove ground electrode design fires leaner mixtures than conventional plugsPrecision machine-rolled threads reduce seizing and cross-threading in delicate aluminum headsWide range of part numbers for thousands of applications, including classic and collector carsLasts twice as long as most conventional plugsWithstands temperatures greater than 4000 Fahrenheit
