SRAM 28T DIRECT 6mm BLACK 11sCompatible with: X1 (with removable spider only), X9, X0, XX, X01, XX1 Saves 25 50g compared to standard spider and chainring design Tall square teeth edges engage the chain earlier than traditional triangle shaped teeth Designed with mud clearing recesses for the inner chain links and rollers Fully CNC AL chainrings GXP uses 6mm offset BB30 uses 0mm offset