Shimano Tourney FC-TY501 Triple Front Chainwheel 170mm Black Chainguard 24-34-42TThe Shimano FC-TY501 Tourney Front Chainwheel has three chainrings and is compatible with 6, 7, or 8 speed rear cassettes. This square constructed crank uses a BB-UN100 Bottom Bracket. The chainring sizes available are 24-34-42T. Available in Arm Lengths of 170mm and 175mm in Black.689228634046