• You Choose Size: 15, 16, 17 or 18 tooth
• This NEW 3/32" cog is perfect for your fixed gear conversion
• You can run a 1/2" x 3/32" or 1/2" x1/8" chain on this cog
• Fits 24 x 1.37 english right hand threaded hubs
• Standard track cog: Formula, Shimano, Joytech etc.
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JOYTECH has been making high-quality hubs for years and is one of the big manufacturers that supply hubs to bike manufactures (Trek, Cannondale, Specialized etc.) for many of their bikes.