Economical and functional Fixed cogs.CNC machine finished from pressed hot rolled mill steel plate.Consistent and durable.Narrow 3/32\" teeth (can run on 1-9speed chains)Fits regular 1.37\" x 24Tpi. hubs.Chrome plated finish.13T- 26g14T - 32g15T - 40g16T - 48g17 - 57g18 - 64g.Note: General Fixed cog check:for correct fixed use, the fixed cog should NEVER move on the hub when pedal force is applied in both directions. i.e. if the cog moves, then something is wrong. Continued use with a fixed cog that moves will result in damage to the hub.