Iridium spark plugs CR8EHIX-9, set of 4, used - Model: CR8EHIX-9 - Quantity: 4 - Type: Iridium spark plugs - Condition: Used Thank you for viewing. These are four spark plugs that were used on a CBR600F. They were used for approximately 2 years and 10,000 kilometers. I didn't feel any problems with them until I removed them.