BB-MT800-P DEORE XT BOTTOM BRACKET -More durable chainwheel teeth. -New 3D composite- chain ring's teeth composition is optimized for each chainwheel load out (1x11, 2x11 & 3x11) with steel driving gear teeth and aluminum support gears. -Lose ratio gear combination for minimum shifting gap and maintaining rhythm. -Improved driving rigidity. -Enhanced chain retention. -Various choices for bike and riding style. -Better sealing and better rotation. 1009901(004 005)2/9