Forte Single-Speed Conversion Kit This kit easily converts most freehub gear systems into a single speed system Going single speed saves on weight, simplifies your drivetrain, increases efficiency and makes your bike a heck of a lot easier to maintain Smooth and quiet operation Includes a Forte chain tensioner, eight spacers of 4.5mm width and three spacers of 3mm width (spacers fit Shimano compatible freehub bodies) Also includes three cogs: 16, 18 and 20 tooth, Shimano compatible cassette lockring and detailed instructions