Convert any normal HG freehub wheel into a Singlespeed drive\n CrMo cog with 7mm thick Hyperglidespline, 1.8mm tooth thickness\n Range of different sized aluminum spacers for fine tuning chainline \n Includes 13t cog, alloy lockring, and 7 spacers: 2) 10mm, 1) 5mm, 4) 3mm