Best Singlespeed cogs(sprockets) on the market. Thanks to the unique tooth shape, narrow-wide profile and perfect roundness these sprockets will outlast any other aluminium counterpart. 23gCompatibilityFits to almost every hub on the market. Please note that some freehubs may be a bit out of tolerance, so the cog may fit tight in such case. This is absolutely normal.Chain compatibility1X, 6/7/8/9/10/11spd chains. To utilize narrow-wide feature please use 9/10/11spd chain. (Not compatible with halflink chains.)Each tooth is much wider and "square like" compared to a commonly used shape. Addition of narrow/wide profile, taken from our award winning Sram spiderless chainring, gives additional teeth strength and offers greater chain retention if a tensioner or chain gets loose while riding. This is the first cog on the market offering such a feature.Cog fits "Shimano type" freehub bodies and offers a 7mm thick base to prevent the damage of alloy freehub under heavy loads. The teeth are cen