E3 Spark Plug E3.12 Lawn and Garden Spark Plug, Pack of 1 Near elimination of performance inhibiting carbon deposits, dramatically longer plug life and limited warranty for the lifetime of the first engine the plug is installed in DiamondFire electrode technology that creates a superior spark and resulting flame front extending further into the cylinder, producing more localized pressure Significant potential power increase: &gt; 6% to 12% (depending on engine class) Significant potential fuel efficiency improvement: &gt; 4% to 13% (depending on engine class) Drastic potential emissions reduction when used in 2 and 4-stroke engines (after 50 hours): 58% CO emissions reduction, 42% hydrocarbon reduction