The Autolite 766 Copper Resistor Spark Plug is the perfect choice for reliable engine performance. With Autolite®'s advanced technology, this spark plug offers quick starts, good fuel economy and smooth acceleration. The one-piece terminal stud provides a reliable connection and the high alumina multi-rib insulator helps prevent flash-over which can lead to misfires. The heat-fused glass composite resistor center seal provides high performance EMI noise suppression and a 100 percent leak-proof seal. The solid copper core center electrode ensures optimal thermal and electrical conductivity for better performance in all driving conditions. The high nickel alloy side electrode resists electrical and chemical wear, providing excellent durability. With a 2 year limited warranty, Autolite 766 Copper Resistor Spark Plug is the ideal choice for long lasting performance. Autolite's 766 Copper Resistor Spark Plug is the perfect solution for smooth and consistent engine operation.