This is a (4 pack!)The NGK CR9EIX (stock no. 3521) Iridium IX spark plug is a high-performance plug designed for a variety of engines, particularly in powersports applications. It is compatible with many popular models from manufacturers such as: Kawasaki: Various models including the Z series and ZX-6R. Yamaha: Various YZF models. Suzuki: GSX-R series. Polaris: Ranger 900, RZR 570, and RZR 900 models. Piaggio It is also used in some specific car models, such as certain Mitsubishi Lancers
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