Fouriers Fixed Gear Cog Threaded 17/18/19/20/21/22T Single 1/8"or 3/32" 5 Colors

Available Size :17T/18T//19T/20T/21T/22T. If your current Cog is 1/8", you can chose 1/8" & 3/32" Cog both. If your current Cog is 3/32", you only can chose3/32".

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