Shimano XT B.B-BB-MT800

-Improved driving rigidity

-Close ratio gear combination for minimum shifting gap and maintaining rhythm

-Enhanced chain retention

-Better sealing and better rotation

-Various choices for bike and riding style

-More durable chainwheel teeth

-New 3D composite chain ring's teeth composition is optimized for each chainwheel --load out with steel driving gear teeth and aluminum support gears

-Average weight: 68.2 g