This is extremely good value crank from the Shimano Tourney Series, with its translation and durability Ideal for MTB and trekking use. It has three chain rings for 6/7/8 speed chains and a solid square socket (inner bearing sold separately). The spool is also compatible with chain: Yes. • Intended use: MTB • Features: - - Steel chain rings - Case Width - Side to Side: 68/73 mm •; Package Content: FC TY501 crank with chain rings, without inner bearing chain rings • - Number Chain Rings: 3 •; Gear Ratio: 48-38-28 teeth crank •, axle Socket: Square •; Chain line: 47.5 mm Chain Guard •; Chain protection ring •; Chain guard compatible