Fitment:Spark plugs compatible with Yamaha FZS1000 FZ1 for YZF-R1 for FZS600 FZ6 for YZF600R for SuzukiGSX-R600 for GSX-R750 for GSX1300R Hayabusa for GSX-R1000 for Kawasaki ZX600 Ninja ZX-6R for ZX900 Ninja ZX-9R（Please enter your vehicle in your Amazon Garage above to see if this spark plugs is compatible with your vehicle） OEM Part Number: Replaces for CR9EIX, 3521, CR7E, CR8E, G57C, G59C, 6263, CR9E (For a detailed list of applicable models, please see the product images and product details page) Premium Material：Iridium spark plugs offer superior performance through their ultra-hard iridium tip, which provides a stronger, more consistent spark for optimized combustion, enhanced reliability, and extended lifespan compared to other materials Exceptional Fuel Efficiency：With a 0.6 mm fine wire iridium center tip and precision laser welding, our spark plugs ensure a focused, consistent spark. This advanced design significantly improves combustion efficiency, resulting in both peak engine performance and minimized fuel use Extended Change Interval：Features an ultra-fine iridium center electrode tip, providing superior durability and resistance to wear, ensuring a significantly longer lifespan of 100,000 miles or more Yeoflagtrade Automotive Replacement Spark Plug Pack is engineered with an iridium-enhanced center electrode and fine-wire design, which increases ignitability and provides consistent production of optimal combustion for engine performance