Shimano Alfine Chainset 45T 170mm With Chainguard Singlespeed FC-S501

The Alfine chainset is a light weight sleek 2-piece design using the proven external bottom bracket system 2-piece design is both lightweight and stiff for optimum power transfer Built in single sided chain guard 170 mm crank arm length Chainring is for use with 9-speed chains and CS-S500 rear sprocket BS thread bottom bracket included for 42.7 mm chain line 5-arm 130 PCD Product Type: Chainsets Speed: Single Speed Discipline: Urban and Trekking Colour: Black Ratio: 45T Length: 170 mm