BB30 bottom bracket, 68/73mm, 42mm, 30mm, Steel, BlackDESCRIPTION BB30 named for its required spindle size narrows Q factor, increases ankle clearance, and ups bearing durability. Along with a 30 mm spindle, it requires an oversized 68mm or 73mm bottom bracket shell and PressFit bearings held in place by snap rings. BB FRAME INTERFACE BB30 CHAINLINE n a SPINDLE LENGTH n a SUPPORT E TYPE FD n a CRANK BB INTERFACE BB30 BEARING TYPE Standard SPINDLE DIAMETER 30mm CUP MATERIAL n a, Plastic