SRAM XX1 11-Speed BB30 156 Crankset New tooth profile alternates thickness by inner and outer links providing maximum chain control 175mm 32T BB30 156 Q/Factor Carbon arms with forged aluminum spider CNC machined rings Weight 650 grams with BBapprox BB not included Must be used in conjunction with SRAMs XX1 complete group rear derailleur cassette shifter chain cranks chainrings