Fsa bb30 mtb bottom bracket os7000bb30 mtb uses the same direct fit bottom bracket and cir clip design as bb30 bb30 mtb uses the 30mm inner diameter id bearing for cranksets with a 30mm diameter od alloy spindle features material chrome steel bb30 cartridge bearings bb shell width 6873mm for mtb includes cir clips and bearing covers weight 63gbuyfsa componentsfrom chain reaction cycles the worlds largest online bike store