Product name: BB middle axis Type no .: BB30 / PF30 / BB386 Rule grid: 42/24 mm, 46/24 mm, 46/30 mm Product color: black Material: CNC aluminum alloy Suitable for five-sided length 68mm / 73mm After conversion, a common 24mm core hollow crankset can be installed There is a pillow ring, according to the actual situation, to choose between the pad and not Package list: 1pcs