The result of independent research and testing suggests that using E3 car spark plugs in your vehicle can increase horsepower when compared to more conventional spark plugs. Our patented Edge-to-Edge electrode outperformed other plug designs, including some premium spark plugs offered by the major manufacturers. Plus, E3 automotive spark plugs will continue to offer that "like-new" performance over the long haul and help to extend the life of your car's engine. Regardless of the brand, model or style of the vehicle that you drive, our plugs are designed to deliver an optimum spark to your car's new or aging engine. Developed in conjunction with researchers from leading universities, we designed our car spark plug to create a faster flame front, so the unburned air-fuel mixtures that would normally pass into the engine's exhaust system experience a more complete burn. Isn't it about time to put the DiamondFire power of our car spark plugs to work in your car, SUV, minivan, truck, motorcycle, snowmobile or ATV?Sold Individually.