RK Racing Chain 4067-030W Steel Rear Sprocket and 530XSOZ1 Chain 20,000 Mile Warranty Kit Fits: Yamaha YZF-R6/YZF-R6S 03-05/06-09 20,000 mile warranty kit contains: 16 tooth chromoly front sprocket; 48 tooth steel rear sprocket; and RK 530XSOZ1-116 link chain RK's new XSO chains offer quality, performance and unbeatable value, for all but the most demanding high performance application Viewed in cross-section, the RK 'RX-ring' has two lubrication pools and seal points versus the single seal point/pool design of a regular O-ring chain This high mileage performance kit features precision cut case hardened steel sprockets with matched OE gearing and RK's XSO or XW sealed ring chain; warranted to provide 20,000 miles of street use (racing and chain neglect will void warranty)