05-2008 Honda 400EX TRX400EX Yellow Non O-Ring Chain & Silver Sprocket 14/39 94L 14 Tooth Front Sprocket, 39 Tooth Rear Sprocket and 520-94L Yellow Non-O-Ring Chain All Race-Driven sprockets meet or exceed OEM specifications and use hardened S45C steel. Non-O-Ring chain doesn't have o-rings between the links so it is lighter, thinner and has less drag. Fits 2005 2006 2007 2008 Honda TRX400EX