A-Premium Set of 8 Ignition Coil Pack and Iridium Spark Plugs Compatible with Chevrolet Silverado 1500, Silverado 1500 LD, Tahoe, Camaro, Suburban & GMC Sierra 1500, Yukon & Cadillac Escalade
[Iridium spark plug]: Iridium is a type of refined alloy which is highly suitable to be used as the materials of the central electrode in a spark plug. It extends the life of the spark plug nearly threefold, ensures a more stable idle speed of the engine, and delivers a super performance to the engine with improved fuel efficiency, reduced emissions and faster starting up.