2005-2008 Honda Sportrax 400EX TRX400EX O-Ring Chain & Silver Sprocket 15/38 94L 15 Tooth Front Sprocket, 38 Tooth Rear Sprocket and 520-94L O-Ring Chain All Race-Driven sprockets meet or exceed OEM specifications and use hardened S45C steel. O-Ring Chain helps keep the pins lubricated which reduces friction and helps the chain last longer. Fits 2005 2006 2007 2008 Honda TRX400EX